kraken/stdlib/interpreter.krak

import mem:*
import math:*
import map:*
import stack:*
import str:*
import util:*
import tree:*
import symbol:*
import ast_nodes:*
import type:*
import os:*
// for is_dot_style_method_call
import pass_common:*

adt value {
    boolean: bool,
    character: char,
    ucharacter: uchar,
    short_int: short,
    ushort_int: ushort,
    integer: int,
    uinteger: uint,
    long_int: long,
    ulong_int: ulong,
    floating: float,
    double_precision: double,
    void_nothing,
    pointer: pair<*void,*type>,
    object_like: pair<*void,*type>,
    variable: pair<*void,*type>,
    function: pair<*ast_node,*map<*ast_node,value>>
}
adt control_flow {
    nor,
    con,
    bre,
    ret
}

// note that there is not object_like, variable, or pointer raw_to_value
fun raw_to_value(data:bool): value
    return value::boolean(data)
fun raw_to_value(data:char): value
    return value::character(data)
fun raw_to_value(data:uchar): value
    return value::ucharacter(data)
fun raw_to_value(data:short): value
    return value::short_int(data)
fun raw_to_value(data:ushort): value
    return value::ushort_int(data)
fun raw_to_value(data:int): value
    return value::integer(data)
fun raw_to_value(data:uint): value
    return value::uinteger(data)
fun raw_to_value(data:long): value
    return value::long_int(data)
fun raw_to_value(data:ulong): value
    return value::ulong_int(data)
fun raw_to_value(data:float): value
    return value::floating(data)
fun raw_to_value(data:double): value
    return value::double_precision(data)

fun wrap_value(val: *ast_node): value {
    var value_str = val->value.string_value
    var value_type = val->value.value_type
    if (value_str[0] == '"') { // " // Comment hack for emacs now
        var to_ret = str()
        // triple quoted strings
        if (value_str[1] == '"' && value_str.length() > 2 && value_str[2] == '"')
            value_str = value_str.slice(3,-4)
        else
            value_str = value_str.slice(1,-2)
        for (var i = 0; i < value_str.length()-1; i++;) {
            if (value_str[i] == '\\' && value_str[i+1] == 'n') {
                to_ret += '\n'
                i++
            } else if (value_str[i] == '\\' && value_str[i+1] == 't') {
                to_ret += '\t'
                i++
            } else if (value_str[i] == '\\' && value_str[i+1] == '\\') {
                to_ret += '\\'
                i++
            } else if (i == value_str.length()-2) {
                to_ret += value_str[i]
                to_ret += value_str[i+1]
            } else {
                to_ret += value_str[i]
            }
        }
        // if there was only one character
        if (value_str.length() == 1)
            to_ret = value_str
        return value::pointer(make_pair((to_ret.toCharArray()) cast *void, get_ast_type(val)))
    } else if (value_str[0] == '\'') //'// lol, comment hack for vim syntax highlighting (my fault, of course)
        return value::character(value_str[1])
    else if (value_str == "true")
        return value::boolean(true)
    else if (value_str == "false")
        return value::boolean(false)
    else {
        var contains_dot = false
        for (var i = 0; i < value_str.length(); i++;) {
            if (value_str[i] == '.') {
                contains_dot = true
                break
            }
        }
        if (contains_dot)
            if (value_str[value_str.length()-1] == 'f')
                return value::floating((string_to_double(value_str.slice(0,-2))) cast float)
            else
                if (value_str[value_str.length()-1] == 'd')
                    return value::double_precision(string_to_double(value_str.slice(0,-2)))
                else
                    return value::double_precision(string_to_double(value_str))
        else {
            match(value_type->base) {
                base_type::character() return value::character(string_to_num<char>(value_str))
                base_type::ucharacter() return value::ucharacter(string_to_num<uchar>(value_str))
                base_type::short_int() return value::short_int(string_to_num<short>(value_str))
                base_type::ushort_int() return value::ushort_int(string_to_num<ushort>(value_str))
                base_type::integer() return value::integer(string_to_num<int>(value_str))
                base_type::uinteger() return value::uinteger(string_to_num<uint>(value_str))
                base_type::long_int() return value::long_int(string_to_num<long>(value_str))
                base_type::ulong_int() return value::ulong_int(string_to_num<ulong>(value_str))
            }
        }
    }
    error("Could not wrap value")
    return value::void_nothing()
}
fun unwrap_value(val: value): *ast_node {
    // str, char, bool, floating
    var value_string = str()
    match (get_real_value(val)) {
        value::boolean(data) value_string = to_string(data)
        value::character(data) value_string = to_string(data)
        value::ucharacter(data) value_string = to_string(data)
        value::short_int(data) value_string = to_string(data)
        value::ushort_int(data) value_string = to_string(data)
        value::integer(data) value_string = to_string(data)
        value::uinteger(data) value_string = to_string(data)
        value::long_int(data) value_string = to_string(data)
        value::ulong_int(data) value_string = to_string(data)
        value::floating(data) value_string = to_string(data)
        value::double_precision(data) value_string = to_string(data)
        value::void_nothing() error("trying to unwrap a void into an _value")
        value::pointer(point) {
            if (point.second->base == base_type::character() && point.second->indirection == 1)
                value_string = str("\"") + str((point.first) cast *char) + "\""
            else
                error("trying to unwrap a pointer into an _value")
        }
        value::object_like(ob) error("trying to unwrap an object_like into an _value")
        value::function(fn) error("trying to unwrap a function into an _value")
    }
    return _value(value_string, get_type_from_primitive_value(get_real_value(val)))
}

fun is_boolean(it: value): bool { match(it) { value::boolean(var) return true; } return false; }
fun is_character(it: value): bool { match(it) { value::character(var) return true; } return false; }
fun is_ucharacter(it: value): bool { match(it) { value::ucharacter(var) return true; } return false; }
fun is_short_int(it: value): bool { match(it) { value::short_int(var) return true; } return false; }
fun is_ushort_int(it: value): bool { match(it) { value::ushort_int(var) return true; } return false; }
fun is_integer(it: value): bool { match(it) { value::integer(var) return true; } return false; }
fun is_uinteger(it: value): bool { match(it) { value::uinteger(var) return true; } return false; }
fun is_long_int(it: value): bool { match(it) { value::long_int(var) return true; } return false; }
fun is_ulong_int(it: value): bool { match(it) { value::ulong_int(var) return true; } return false; }
fun is_floating(it: value): bool { match(it) { value::floating(var) return true; } return false; }
fun is_double_precision(it: value): bool { match(it) { value::double_precision(var) return true; } return false; }
fun is_void_nothing(it: value): bool { match(it) { value::void_nothing() return true; } return false; }
fun is_pointer(it: value): bool { match(it) { value::pointer(var) return true; } return false; }
fun is_object_like(it: value): bool { match(it) { value::object_like(var) return true; } return false; }
fun is_variable(it: value): bool { match(it) { value::variable(var) return true; } return false; }
fun is_function(it: value): bool { match(it) { value::function(var) return true; } return false; }

fun print_value(v: ref value) {
    match (get_real_value(v)) {
        value::boolean(data) println(data)
        value::character(data) println(data)
        value::ucharacter(data) println(data)
        value::short_int(data) println(data)
        value::ushort_int(data) println(data)
        value::integer(data) println(data)
        value::uinteger(data) println(data)
        value::long_int(data) println(data)
        value::ulong_int(data) println(data)
        value::floating(data) println(data)
        value::double_precision(data) println(data)
        value::void_nothing() println("void")
        value::pointer(var) println("pointer")
        value::object_like(var) println("object_like")
        value::variable(var) println("variable")
        value::function(var) println("function")
    }
}
fun truthy(v: ref value):bool {
    match (get_real_value(v)) {
        value::boolean(data) return data
        value::character(data) return data != 0
        value::ucharacter(data) return data != 0
        value::short_int(data) return data != 0
        value::ushort_int(data) return data != 0
        value::integer(data) return data != 0
        value::uinteger(data) return data != 0
        value::long_int(data) return data != 0
        value::ulong_int(data) return data != 0
        value::floating(data) return data != 0
        value::double_precision(data) return data != 0
        value::pointer(data) return data.first != 0
    }
    error("untruthy value")
}
fun do_basic_op(func_name: str, a: value, b: value): value {
    match (get_real_value(a)) {
        value::boolean(av) return do_basic_op_second_half(func_name, av, b, null<type>())
        value::character(av) return do_basic_op_second_half(func_name, av, b, null<type>())
        value::ucharacter(av) return do_basic_op_second_half(func_name, av, b, null<type>())
        value::short_int(av) return do_basic_op_second_half(func_name, av, b, null<type>())
        value::ushort_int(av) return do_basic_op_second_half(func_name, av, b, null<type>())
        value::integer(av) return do_basic_op_second_half(func_name, av, b, null<type>())
        value::uinteger(av) return do_basic_op_second_half(func_name, av, b, null<type>())
        value::long_int(av) return do_basic_op_second_half(func_name, av, b, null<type>())
        value::ulong_int(av) return do_basic_op_second_half(func_name, av, b, null<type>())
        value::floating(av) return do_basic_floating_op_second_half(func_name, av, b, null<type>())
        value::double_precision(av) return do_basic_floating_op_second_half(func_name, av, b, null<type>())
        value::pointer(av) {
            var real_b = get_real_value(b)
            if (func_name == "==") {
                if (!is_pointer(real_b)) {
                    print("equality between pointer and not pointer: ")
                    print_value(real_b)
                    error(":/")
                }
                return value::boolean(av.first == real_b.pointer.first)
            } else if (func_name == "!=") {
                if (!is_pointer(real_b)) {
                    print("inequality between pointer and not pointer: ")
                    print_value(real_b)
                    error(":/")
                }
                return value::boolean(av.first != real_b.pointer.first)
            }
            var inc_in_bytes = cast_value(b, type_ptr(base_type::ulong_int())).ulong_int * type_size(av.second->clone_with_decreased_indirection())
            var ptr = null<void>()
            if (func_name == "+") {
                ptr = ((av.first) cast *char + inc_in_bytes) cast *void
            } else if (func_name == "-") {
                ptr = ((av.first) cast *char - inc_in_bytes) cast *void
            } else {
                println(str("pointer arithmatic is not +, -, ==, or !=: ") + func_name + ", b is: ")
                print_value(b)
                error(str("pointer arithmatic is not +, -, ==, or !=: ") + func_name)
            }
            return value::pointer(make_pair(ptr, av.second))
        }
        value::void_nothing() error(str("basic op called with void_nothing as first param: ") + func_name)
        value::object_like() error(str("basic op called with object_like as first param: ") + func_name)
    }
    error(str("basic op called with something wrong as first param: ") + func_name)
}
fun do_basic_op_second_half<T>(func_name: str, av: T, b: value, ptr_type: *type): value {
    // because of the trickery in do_basic_op, if either param is a pointer, it's b
    match (get_real_value(b)) {
        value::boolean(bv) return do_op(func_name, av, bv, ptr_type)
        value::character(bv) return do_op(func_name, av, bv, ptr_type)
        value::ucharacter(bv) return do_op(func_name, av, bv, ptr_type)
        value::short_int(bv) return do_op(func_name, av, bv, ptr_type)
        value::ushort_int(bv) return do_op(func_name, av, bv, ptr_type)
        value::integer(bv) return do_op(func_name, av, bv, ptr_type)
        value::uinteger(bv) return do_op(func_name, av, bv, ptr_type)
        value::long_int(bv) return do_op(func_name, av, bv, ptr_type)
        value::ulong_int(bv) return do_op(func_name, av, bv, ptr_type)
        value::floating(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::double_precision(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::void_nothing() error(str("basic op called with void_nothing as second param: ") + func_name)
        value::object_like() error(str("basic op called with object_like as second param: ") + func_name)
        // if one is a pointer, we want it to be a
        value::pointer(bv) return do_basic_op(func_name, b, raw_to_value(av))
    }
    print_value(b)
    error(str("basic op called with something wrong as second param: ") + func_name)
}
fun do_op<T,U>(op: str, a: T, b: U, ptr_type: *type): value {
    if (op == "+") return raw_to_value(a + b)
    if (op == "-") return raw_to_value(a - b)
    if (op == "*") return raw_to_value(a * b)
    if (op == "/") return raw_to_value(a / b)
    if (op == "<") return raw_to_value(a < b)
    if (op == ">") return raw_to_value(a > b)
    if (op == "<=") return raw_to_value(a <= b)
    if (op == ">=") return raw_to_value(a >= b)
    if (op == "==") return raw_to_value(a == b)
    if (op == "!=") return raw_to_value(a != b)
    if (op == "%") return raw_to_value(a % b)
    if (op == "^") return raw_to_value(a ^ b)
    if (op == "|") return raw_to_value(a | b)
    if (op == "&") return raw_to_value(a & b)
    error(("Invalid op: ") + op)
}
fun do_basic_floating_op_second_half<T>(func_name: str, av: T, b: value, ptr_type: *type): value {
    // because of the trickery in do_basic_op, if either param is a pointer, it's b
    match (get_real_value(b)) {
        value::boolean(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::character(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::ucharacter(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::short_int(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::ushort_int(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::integer(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::uinteger(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::long_int(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::ulong_int(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::floating(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::double_precision(bv) return do_floating_op(func_name, av, bv, ptr_type)
        value::void_nothing() error(str("basic op called with void_nothing as second param: ") + func_name)
        value::object_like() error(str("basic op called with object_like as second param: ") + func_name)
        // if one is a pointer, we want it to be a
        value::pointer(bv) return do_basic_op(func_name, b, raw_to_value(av))
    }
    print_value(b)
    error(str("basic op called with something wrong as second param: ") + func_name)
}
fun do_floating_op<T,U>(op: str, a: T, b: U, ptr_type: *type): value {
    if (op == "+") return raw_to_value(a + b)
    if (op == "-") return raw_to_value(a - b)
    if (op == "*") return raw_to_value(a * b)
    if (op == "/") return raw_to_value(a / b)
    if (op == "<") return raw_to_value(a < b)
    if (op == ">") return raw_to_value(a > b)
    if (op == "<=") return raw_to_value(a <= b)
    if (op == ">=") return raw_to_value(a >= b)
    if (op == "==") return raw_to_value(a == b)
    if (op == "!=") return raw_to_value(a != b)
    error(("Invalid op: ") + op)
}
// the ref special case is interesting because it also means we have to take in the value by ref
fun store_into_variable(to: ref value, from: value) {
    assert(is_variable(to), "trying to store into not variable")
    var variable = to.variable
    // NOTE
    // we have a special case here - we allow assigning to a ref from a pointer, as this is used in adt_lower
    if (variable.second->is_ref && is_pointer(from) && variable.second->clone_with_increased_indirection()->equality(from.pointer.second, false)) {
        to.variable.first = from.pointer.first
        return;
    }
    // check for indirection
    if (variable.second->indirection) {
        assert(is_pointer(from), "mismatching assignemnt types - from is not pointer")
        *(variable.first) cast **void = from.pointer.first
        return;
    }
    // TODO - check to make sure that we don't have to cast pre assign (perhaps alwyas send through the cast?)
    match (variable.second->base) {
        base_type::object() { assert(is_object_like(from), "mismatching assignemnt types - from is not object"); memmove(variable.first, from.object_like.first, type_size(from.object_like.second)); }
        base_type::function() { assert(is_function(from), "mismatching assignemnt types - from is not function"); *(variable.first) cast *pair<*ast_node, *map<*ast_node,value>> = from.function; }
        base_type::boolean() { assert(is_boolean(from), "mismatching assignemnt types - from is not boolean"); *(variable.first) cast *bool = from.boolean; }
        base_type::character() { assert(is_character(from), "mismatching assignemnt types - from is not character"); *(variable.first) cast *char = from.character; }
        base_type::ucharacter() { assert(is_ucharacter(from), "mismatching assignemnt types - from is not ucharacter"); *(variable.first) cast *uchar = from.ucharacter; }
        base_type::short_int() { assert(is_short_int(from), "mismatching assignemnt types - from is not short_int"); *(variable.first) cast *short = from.short_int; }
        base_type::ushort_int() { assert(is_ushort_int(from), "mismatching assignemnt types - from is not ushort_int"); *(variable.first) cast *ushort = from.ushort_int; }
        base_type::integer() { assert(is_integer(from), "mismatching assignemnt types - from is not integer"); *(variable.first) cast *int = from.integer; }
        base_type::uinteger() { assert(is_uinteger(from), "mismatching assignemnt types - from is not uinteger"); *(variable.first) cast *uint = from.uinteger; }
        base_type::long_int() { assert(is_long_int(from), "mismatching assignemnt types - from is not long_int"); *(variable.first) cast *long = from.long_int; }
        base_type::ulong_int() { assert(is_ulong_int(from), "mismatching assignemnt types - from is not ulong_int"); *(variable.first) cast *ulong = from.ulong_int; }
        base_type::floating() { assert(is_floating(from), "mismatching assignemnt types - from is not floating"); *(variable.first) cast *float = from.floating; }
        base_type::double_precision() { assert(is_double_precision(from), "mismatching assignemnt types - from is not double"); *(variable.first) cast *double = from.double_precision; }
    }
}
fun get_real_value(v: value): value {
    if (!is_variable(v))
        return v
    var variable = v.variable
    var var_ptr = variable.first
    var var_type = variable.second
    // step through indirection first
    if (var_type->indirection)
        return value::pointer(make_pair(*(var_ptr) cast **void, var_type))
    match (var_type->base) {
        base_type::object() return value::object_like(make_pair(var_ptr, var_type))
        base_type::boolean() return value::boolean(*(var_ptr) cast *bool)
        base_type::character() return value::character(*(var_ptr) cast *char)
        base_type::ucharacter() return value::ucharacter(*(var_ptr) cast *uchar)
        base_type::short_int() return value::short_int(*(var_ptr) cast *short)
        base_type::ushort_int() return value::ushort_int(*(var_ptr) cast *ushort)
        base_type::integer() return value::integer(*(var_ptr) cast *int)
        base_type::uinteger() return value::uinteger(*(var_ptr) cast *uint)
        base_type::long_int() return value::long_int(*(var_ptr) cast *long)
        base_type::ulong_int() return value::ulong_int(*(var_ptr) cast *ulong)
        base_type::floating() return value::floating(*(var_ptr) cast *float)
        base_type::double_precision() return value::double_precision(*(var_ptr) cast *double)
        base_type::function() return value::function(*(var_ptr) cast *pair<*ast_node,*map<*ast_node,value>>)
    }
    error(str("Cannot get real value from variable: ") + variable.second->to_string())
}
fun wrap_into_variable(v: value): value {
    if (is_variable(v))
        return v
    if (is_object_like(v))
        return value::variable(make_pair(v.object_like.first, v.object_like.second))
    var variable_type = get_type_from_primitive_value(v)
    var to_ret = value::variable(make_pair(malloc(type_size(variable_type)), variable_type))
    store_into_variable(to_ret, v)
    return to_ret
}
fun get_type_from_primitive_value(v: value): *type {
    match (v) {
        value::boolean(data) return type_ptr(base_type::boolean())
        value::character(data) return type_ptr(base_type::character())
        value::ucharacter(data) return type_ptr(base_type::ucharacter())
        value::short_int(data) return type_ptr(base_type::short_int())
        value::ushort_int(data) return type_ptr(base_type::ushort_int())
        value::integer(data) return type_ptr(base_type::integer())
        value::uinteger(data) return type_ptr(base_type::uinteger())
        value::long_int(data) return type_ptr(base_type::long_int())
        value::ulong_int(data) return type_ptr(base_type::ulong_int())
        value::floating(data) return type_ptr(base_type::floating())
        value::double_precision(data) return type_ptr(base_type::double_precision())
        value::pointer(data) return data.second
        value::void_nothing() return type_ptr(base_type::void_return())
        value::function(data) return data.first->function.type
    }
    println("Bad get_type_from_primitive_value!")
    print_value(v)
    error("Called get_type_from_primitive_value with non-primitive value (maybe in a variable?)")
}
fun cast_value(v: value, to_type: *type): value {
    if (to_type->indirection) {
        match (get_real_value(v)) {
            value::boolean(data) return value::pointer(make_pair((data) cast *void, to_type))
            value::character(data) return value::pointer(make_pair((data) cast *void, to_type))
            value::ucharacter(data) return value::pointer(make_pair((data) cast *void, to_type))
            value::short_int(data) return value::pointer(make_pair((data) cast *void, to_type))
            value::ushort_int(data) return value::pointer(make_pair((data) cast *void, to_type))
            value::integer(data) return value::pointer(make_pair((data) cast *void, to_type))
            value::uinteger(data) return value::pointer(make_pair((data) cast *void, to_type))
            value::long_int(data) return value::pointer(make_pair((data) cast *void, to_type))
            value::ulong_int(data) return value::pointer(make_pair((data) cast *void, to_type))
            // floats and anything object_like are illegal to cast from
            /*value::floating(data) return value::pointer(make_pair((data) cast *void, to_type))*/
            /*value::double_precision(data) return value::pointer(make_pair((data) cast *void, to_type))*/
            value::pointer(data) return value::pointer(make_pair(data.first, to_type))
        }
        error("Bad cast to pointer")
    }
    match (to_type->base) {
        // object_like can't be casted
        base_type::boolean() return cast_value_second_half<bool>(v)
        base_type::character() return cast_value_second_half<char>(v)
        base_type::ucharacter() return cast_value_second_half<uchar>(v)
        base_type::short_int() return cast_value_second_half<short>(v)
        base_type::ushort_int() return cast_value_second_half<ushort>(v)
        base_type::integer() return cast_value_second_half<int>(v)
        base_type::uinteger() return cast_value_second_half<uint>(v)
        base_type::long_int() return cast_value_second_half<long>(v)
        base_type::ulong_int() return cast_value_second_half<ulong>(v)
        // float and double need their own because it can't go from
        base_type::floating() match (get_real_value(v)) {
            value::boolean(data) return value::floating((data) cast float)
            value::character(data) return value::floating((data) cast float)
            value::ucharacter(data) return value::floating((data) cast float)
            value::short_int(data) return value::floating((data) cast float)
            value::ushort_int(data) return value::floating((data) cast float)
            value::integer(data) return value::floating((data) cast float)
            value::uinteger(data) return value::floating((data) cast float)
            value::long_int(data) return value::floating((data) cast float)
            value::ulong_int(data) return value::floating((data) cast float)
            value::floating(data) return get_real_value(v)
            value::double_precision(data) return value::floating((data) cast float)
        }
        base_type::double_precision() match (get_real_value(v)) {
            value::boolean(data) return value::double_precision((data) cast double)
            value::character(data) return value::double_precision((data) cast double)
            value::ucharacter(data) return value::double_precision((data) cast double)
            value::short_int(data) return value::double_precision((data) cast double)
            value::ushort_int(data) return value::double_precision((data) cast double)
            value::integer(data) return value::double_precision((data) cast double)
            value::uinteger(data) return value::double_precision((data) cast double)
            value::long_int(data) return value::double_precision((data) cast double)
            value::ulong_int(data) return value::double_precision((data) cast double)
            value::floating(data) return value::double_precision((data) cast double)
            value::double_precision(data) return get_real_value(v)
        }
    }
    error(str("Bad cast to ") + to_type->to_string())
}
fun cast_value_second_half<T>(v: value): value {
    match (get_real_value(v)) {
        // object_like can't be casted
        value::boolean(data) return raw_to_value((data) cast T)
        value::character(data) return raw_to_value((data) cast T)
        value::ucharacter(data) return raw_to_value((data) cast T)
        value::short_int(data) return raw_to_value((data) cast T)
        value::ushort_int(data) return raw_to_value((data) cast T)
        value::integer(data) return raw_to_value((data) cast T)
        value::uinteger(data) return raw_to_value((data) cast T)
        value::long_int(data) return raw_to_value((data) cast T)
        value::ulong_int(data) return raw_to_value((data) cast T)
        value::floating(data) return raw_to_value((data) cast T)
        value::double_precision(data) return raw_to_value((data) cast T)
        value::pointer(data) return raw_to_value((data.first) cast T)
    }
    error("Illegal type to cast cast from")
}
fun type_size(t: *type): ulong
    return type_size_and_alignment(t).first
fun type_size_and_alignment(t: *type): pair<ulong,ulong> {
    if (t->indirection)
        return make_pair(#sizeof<*void>, #sizeof<*void>)
    match (t->base) {
        base_type::object() {
            var total_size: ulong = 0
            var max_size: ulong = 0
            var max_align: ulong = 0
            t->type_def->type_def.variables.for_each(fun(i: *ast_node) {
                var individual = type_size_and_alignment(i->declaration_statement.identifier->identifier.type)
                max_size = max(max_size, individual.first)
                max_align = max(max_align, individual.second)
                // increase total size by the individual size + padding to get alignment
                var padding = 0
                if (individual.second != 0)
                    padding = (individual.second - (total_size % individual.second)) % individual.second
                total_size += individual.first + padding
            })
            if (t->type_def->type_def.is_union)
                total_size = max_size
            // pad the end so that consecutive objects in memory are aligned
            if (max_align != 0)
                total_size += (max_align - (total_size % max_align)) % max_align
            return make_pair(total_size, max_align)
        }
        base_type::function() return make_pair(#sizeof<pair<*ast_node,*map<*ast_node,value>>>, #sizeof<*void>)
        base_type::boolean() return make_pair(#sizeof<bool>, #sizeof<bool>)
        base_type::character() return make_pair(#sizeof<char>, #sizeof<char>)
        base_type::ucharacter() return make_pair(#sizeof<uchar>, #sizeof<uchar>)
        base_type::short_int() return make_pair(#sizeof<short>, #sizeof<short>)
        base_type::ushort_int() return make_pair(#sizeof<ushort>, #sizeof<ushort>)
        base_type::integer() return make_pair(#sizeof<int>, #sizeof<int>)
        base_type::uinteger() return make_pair(#sizeof<uint>, #sizeof<uint>)
        base_type::long_int() return make_pair(#sizeof<long>, #sizeof<long>)
        base_type::ulong_int() return make_pair(#sizeof<ulong>, #sizeof<ulong>)
        base_type::floating() return make_pair(#sizeof<float>, #sizeof<float>)
        base_type::double_precision() return make_pair(#sizeof<double>, #sizeof<double>)
    }
    error(str("Invalid type for type_size: ") + t->to_string())
}
fun offset_into_struct(struct_type: *type, ident: *ast_node): ulong {
    var offset: ulong = 0
    if (struct_type->type_def->type_def.is_union)
        return offset
    for (var i = 0; i < struct_type->type_def->type_def.variables.size; i++;) {
        var size_and_align = type_size_and_alignment(struct_type->type_def->type_def.variables[i]->declaration_statement.identifier->identifier.type)
        var align = size_and_align.second
        if (align != 0)
            offset += (align - (offset % align)) % align
        if (struct_type->type_def->type_def.variables[i]->declaration_statement.identifier == ident)
            break
        else
            offset += size_and_align.first
    }
    return offset
}
// to dereference, we basically take the pointer's value (maybe going through a variable to get it)
// and re-wrap it up into a variable value (so it can be assigned to, etc)
fun dereference_pointer_into_variable(dereference_val: value): value
    return value::variable(make_pair(get_real_value(dereference_val).pointer.first, dereference_val.pointer.second->clone_with_decreased_indirection()))
fun pop_and_free(var_stack: *stack<map<*ast_node, value>>) {
    var_stack->pop().for_each(fun(k: *ast_node, v: value) {
        match(v) {
            value::variable(backing) {
                /*free(backing.first)*/
            }
        }
    })
}

fun call_main(name_ast_map: ref map<str, pair<*tree<symbol>,*ast_node>>) {
    var results = vec<*ast_node>()
    name_ast_map.for_each(fun(key: str, value: pair<*tree<symbol>,*ast_node>) {
        results += scope_lookup(str("main"), value.second)
    })
    if (results.size != 1)
        error(str("wrong number of mains to call: ") + results.size)
    var globals = setup_globals(name_ast_map)
    var result = call_function(results[0], vec<value>(), &globals)
}
fun evaluate_constant_expression(node: *ast_node): value
    return interpret(node, null<stack<map<*ast_node, value>>>(), value::void_nothing(), null<ast_node>(), null<map<*ast_node, value>>()).first
fun evaluate_with_globals(node: *ast_node, globals: *map<*ast_node, value>): value
    return interpret(node, null<stack<map<*ast_node, value>>>(), value::void_nothing(), null<ast_node>(), globals).first
fun setup_globals(name_ast_map: ref map<str, pair<*tree<symbol>,*ast_node>>): map<*ast_node, value> {
    var globals = map<*ast_node, value>()
    name_ast_map.for_each(fun(key: str, value: pair<*tree<symbol>,*ast_node>) {
        value.second->translation_unit.children.for_each(fun(child: *ast_node) {
            if (is_declaration_statement(child)) {
                var declaration = child->declaration_statement
                var identifier = declaration.identifier->identifier
                if (identifier.is_extern) {
                    if (identifier.name == "stderr") {
                        var stderr_type = type_ptr(base_type::void_return(), 1)
                        var stderr_pointer = malloc(type_size(stderr_type))
                        *(stderr_pointer) cast **void = stderr;
                        globals[declaration.identifier] = value::variable(make_pair(stderr_pointer, stderr_type))
                    } else if (identifier.name == "stdin") {
                        var stdin_type = type_ptr(base_type::void_return(), 1)
                        var stdin_pointer = malloc(type_size(stdin_type))
                        *(stdin_pointer) cast **void = stdin;
                        globals[declaration.identifier] = value::variable(make_pair(stdin_pointer, stdin_type))
                    } else {
                        error(str("unknown extern: ") + identifier.name)
                    }
                } else {
                    globals[declaration.identifier] = value::variable(make_pair(calloc(type_size(identifier.type)), identifier.type))
                    if (declaration.expression)
                        store_into_variable(globals[declaration.identifier], get_real_value(interpret(declaration.expression, null<stack<map<*ast_node,value>>>(), value::void_nothing(), null<ast_node>(), null<map<*ast_node,value>>()).first))
                }
            }
        })
    })
    return globals
}
fun interpret_function_call(func_call: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    var func_call_parameters = func_call->function_call.parameters
    var func_call_func = func_call->function_call.func
    var new_enclosing_object = value::void_nothing()
    var dot_style_method_call = is_dot_style_method_call(func_call)
    var possible_closure_map = map<*ast_node,value>()
    // test for function value
    if (!dot_style_method_call && (!is_function(func_call_func) || func_call_func->function.closed_variables.size())) {
        var func_value = get_real_value(interpret(func_call_func, var_stack, enclosing_object, enclosing_func, globals).first)
        func_call_func = func_value.function.first
        possible_closure_map = *func_value.function.second
        // if the closure closes over this, put it as the enclosing object inside the closure
        possible_closure_map.for_each(fun(key: *ast_node, v: value) {
            if (key->identifier.name == "this") {
                new_enclosing_object = get_real_value(dereference_pointer_into_variable(v))
            }
        })
    }
    // note here also that this is likely not a foolproof method
    if (dot_style_method_call) {
        new_enclosing_object = get_real_value(interpret(func_call_func->function_call.parameters[0], var_stack, enclosing_object, enclosing_func, globals).first)
        // do a dereference
        if (is_pointer(new_enclosing_object))
            new_enclosing_object = get_real_value(value::variable(make_pair(new_enclosing_object.pointer.first, new_enclosing_object.pointer.second->clone_with_decreased_indirection())))
        func_call_func = func_call_func->function_call.parameters[1]
    } else if (!is_void_nothing(enclosing_object)) {
        if (method_in_object(func_call_func, enclosing_object.object_like.second->type_def)) {
            // should maybe do something special for closure here
            // copy over old enclosing object
            new_enclosing_object = enclosing_object
        }
    }
    var func_name = func_call_func->function.name
    // some of these have to be done before parameters are evaluated (&&, ||, ., ->)
    if (func_name == "&&" || func_name == "||") {
        error("short circuit still in interpreter")
    } else if (func_name == "." || func_name == "->") {
        var left_side = get_real_value(interpret(func_call_parameters[0], var_stack, enclosing_object, enclosing_func, globals).first)
        var ret_ptr = null<void>()
        if (func_name == "->")
            ret_ptr = ((left_side.pointer.first) cast *char + offset_into_struct(left_side.pointer.second->clone_with_decreased_indirection(), func_call_parameters[1])) cast *void
        else
            ret_ptr = ((left_side.object_like.first) cast *char + offset_into_struct(left_side.object_like.second, func_call_parameters[1])) cast *void
        return make_pair(value::variable(make_pair(ret_ptr, func_call_parameters[1]->identifier.type)), control_flow::nor())
    }
    // so here we either do an operator, call call_func with value parameters, or call call_func with ast_expressions
    // (so we can properly copy_construct if necessary)
    var parameters = vec<value>()
    var parameter_sources = vec<*ast_node>()
    // if we don't have to copy_construct params (is an operator, or has no object params)
    if (func_name == "&" || !func_call_parameters.any_true(fun(p: *ast_node): bool return get_ast_type(p)->is_object() && get_ast_type(p)->indirection == 0;)) {
        parameters = func_call_parameters.map(fun(p: *ast_node): value return interpret(p, var_stack, enclosing_object, enclosing_func, globals).first;)
        if ( parameters.size == 2 && (func_name == "+" || func_name == "-" || func_name == "*" || func_name == "/"
            || func_name == "<" || func_name == ">" || func_name == "<=" || func_name == ">="
            || func_name == "==" || func_name == "!=" || func_name == "%" || func_name == "^"
            || func_name == "|" || func_name == "&"
        ))
            return make_pair(do_basic_op(func_name, parameters[0], parameters[1]), control_flow::nor())
        // do negate by subtracting from zero
        if (func_name == "-")
            return make_pair(do_basic_op_second_half(str("-"), 0, parameters[0], null<type>()), control_flow::nor())
        if (func_name == "!")
            return make_pair(value::boolean(!truthy(get_real_value(parameters[0]))), control_flow::nor())
        if (func_name == "++p" || func_name == "--p") {
            var to_ret = get_real_value(parameters[0])
            store_into_variable(parameters[0], do_basic_op(func_name.slice(0,1), parameters[0], value::integer(1)))
            return make_pair(to_ret, control_flow::nor())
        }
        if (func_name == "++" || func_name == "--") {
            store_into_variable(parameters[0], do_basic_op(func_name.slice(0,1), parameters[0], value::integer(1)))
            return make_pair(get_real_value(parameters[0]), control_flow::nor())
        }
        if (func_name == "&") {
            if (is_variable(parameters[0]))
                return make_pair(value::pointer(make_pair(parameters[0].variable.first, parameters[0].variable.second->clone_with_increased_indirection())), control_flow::nor())
            else if (is_object_like(parameters[0]))
                return make_pair(value::pointer(make_pair(parameters[0].object_like.first, parameters[0].object_like.second->clone_with_increased_indirection())), control_flow::nor())
            else {
                print("can't take address of: ")
                print_value(parameters[0])
                error("Trying to take address of not a variable or object_like")
            }
        }
        if (func_name == "*" || func_name == "[]") {
            var dereference_val = parameters[0]
            if (func_name == "[]")
                dereference_val = do_basic_op(str("+"), parameters[0], parameters[1])
            if (!is_pointer(get_real_value(parameters[0])))
                error("Trying to take dereference not a pointer")
            return make_pair(dereference_pointer_into_variable(dereference_val), control_flow::nor())
        }
        // check for built-in-ish externs (everything the standard library needs)
        if (func_name == "printf" || func_name == "malloc" || func_name == "free" || func_name == "memmove" || func_name == "fflush" || func_name == "snprintf" || func_name == "fopen" || func_name == "fclose" || func_name == "ftell" || func_name == "fseek" || func_name == "fread" || func_name == "fwrite" || func_name == "atan" || func_name == "atan2" || func_name == "acos" || func_name == "asin" || func_name == "tan" || func_name == "cos" || func_name == "sin" || func_name == "fgets" || func_name == "popen" || func_name == "pclose")
            return make_pair(call_built_in_extern(func_name, parameters), control_flow::nor())
        if (!func_call_func->function.body_statement)
            error(str("trying to call unsupported extern function: ") + func_name)
    } else {
        // not the operator & and at least one object like parameter
        parameter_sources = func_call_parameters
    }
    return make_pair(call_function(func_call_func, parameters, parameter_sources, var_stack, possible_closure_map, enclosing_object, new_enclosing_object, enclosing_func, globals), control_flow::nor())
}

fun call_function(func: *ast_node, parameters: vec<value>, globals: *map<*ast_node, value>): value {
    var var_stack = stack<map<*ast_node, value>>()
    var_stack.push(map<*ast_node,value>())
    var result = call_function(func, parameters, vec<*ast_node>(), &var_stack, map<*ast_node,value>(), value::void_nothing(), value::void_nothing(), null<ast_node>(), globals)
    pop_and_free(&var_stack)
    return result
}
// call_function can be called with either parameter values in parameters or ast expressions in parameter_sources
// this is to allow easy function calling if we already have the values (for main, say, or to make our job if it's not
// an operator easier), but we need to be able to be called with ast_expressions too so we can properly copy_construct once
fun call_function(func: *ast_node, parameters: vec<value>, parameter_sources: vec<*ast_node>, var_stack: *stack<map<*ast_node, value>>, possible_closure_map: ref map<*ast_node, value>, enclosing_object: value, new_enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): value {
    // will need adjustment
    if (!is_function(func))
        error("Can't handle not function function calls (can do regular method, is this chained or something?)")
    var func_name = func->function.name
    // do regular function
    // start out with the possible closure map as the highest scope (gloabals checked seperately)
    var new_var_stack = stack(possible_closure_map)
    new_var_stack.push(map<*ast_node,value>())
    // if this is a value based call, pull from parameters
    if (parameter_sources.size == 0) {
        /*println(func_name + " being called with parameter values")*/
        if (parameters.size != func->function.parameters.size)
            error(str("calling function ") + func->function.name + " with wrong number of parameters (values)")
        for (var i = 0; i < parameters.size; i++;) {
            var param_type = get_ast_type(func)->parameter_types[i]
            var param_ident = func->function.parameters[i]
            if (param_type->is_ref) {
                if (is_variable(parameters[i]))
                    new_var_stack.top()[param_ident] = parameters[i]
                else
                    new_var_stack.top()[param_ident] = wrap_into_variable(parameters[i])
            } else {
                new_var_stack.top()[param_ident] = value::variable(make_pair(malloc(type_size(param_type)), param_type))
                store_into_variable(new_var_stack.top()[param_ident], get_real_value(parameters[i]))
            }
        }
    } else {
        // on this side we construct temps in the old var stack, then move it over to the new one so that references resolve correctly
        var_stack->push(map<*ast_node,value>())
        /*println(func_name + " being called with parameter sources")*/
        // need to pull from parameter_sources instead
        if (parameter_sources.size != func->function.parameters.size)
            error(str("calling function ") + func->function.name + " with wrong number of parameters (sources)")
        for (var i = 0; i < parameter_sources.size; i++;) {
            var param_type = get_ast_type(func)->parameter_types[i]
            var param_ident = func->function.parameters[i]
            if (param_type->is_ref) {
                var param = interpret(parameter_sources[i], var_stack, enclosing_object, enclosing_func, globals).first
                if (is_variable(param))
                    new_var_stack.top()[param_ident] = param
                else
                    new_var_stack.top()[param_ident] = wrap_into_variable(param)
            } else {
                new_var_stack.top()[param_ident] = value::variable(make_pair(malloc(type_size(param_type)), param_type))
                store_into_variable(new_var_stack.top()[param_ident], get_real_value(interpret(parameter_sources[i], var_stack, enclosing_object, enclosing_func, globals).first))
            }
        }
    }
    var to_ret = interpret(func->function.body_statement, &new_var_stack, new_enclosing_object, func, globals).first
    // to_ret is on the new_var_stack, likely
    /*pop_and_free(&new_var_stack)*/
    if (parameter_sources.size) {
        // pop off the temporaries if we needed to, but only after destructing any params we needed to
        pop_and_free(var_stack)
    }
    return to_ret
}
fun call_built_in_extern(func_name: str, parameters: vec<value>): value {
    for (var i = 0; i < parameters.size; i++;)
        parameters[i] = get_real_value(parameters[i])
    if (func_name == "printf") {
        assert(parameters.size == 2 && is_pointer(parameters[0]) && is_pointer(parameters[1]), "Calling printf with wrong params")
        printf((parameters[0].pointer.first) cast *char, (parameters[1].pointer.first) cast *char)
        return value::integer(0)
    } else if (func_name == "malloc") {
        assert(parameters.size == 1 && is_ulong_int(parameters[0]), "Calling malloc with wrong params")
        return value::pointer(make_pair(malloc(parameters[0].ulong_int), type_ptr(base_type::void_return())->clone_with_increased_indirection()))
    } else if (func_name == "free") {
        assert(parameters.size == 1 && is_pointer(parameters[0]), "Calling free with wrong params")
        free(parameters[0].pointer.first)
    } else if (func_name == "memmove") {
        assert(parameters.size == 3 && is_pointer(parameters[0]) && is_pointer(parameters[1]) && is_ulong_int(parameters[2]), "Calling memmove with wrong params")
        return value::pointer(make_pair(memmove((parameters[0].pointer.first) cast *void, (parameters[1].pointer.first) cast *void, parameters[2].ulong_int), type_ptr(base_type::void_return(), 1)))
    } else if (func_name == "fflush") {
        assert(parameters.size == 1 && is_integer(parameters[0]), "Calling fflush with wrong params")
        fflush(parameters[0].integer)
    } else if (func_name == "snprintf") {
        assert(parameters.size == 4 && is_pointer(parameters[0]) && is_ulong_int(parameters[1]) && is_pointer(parameters[2]) && is_double_precision(parameters[3]), "Calling snprintf with wrong params")
        return value::integer(snprintf((parameters[0].pointer.first) cast *char, parameters[1].ulong_int, (parameters[2].pointer.first) cast *char, parameters[3].double_precision))
    } else if (func_name == "fopen") {
        assert(parameters.size == 2 && is_pointer(parameters[0]) && is_pointer(parameters[1]), "Calling fopen with wrong params")
        return value::pointer(make_pair(fopen((parameters[0].pointer.first) cast *char, (parameters[1].pointer.first) cast *char), type_ptr(base_type::void_return(), 1)))
    } else if (func_name == "fclose") {
        assert(parameters.size == 1 && is_pointer(parameters[0]), "Calling fclose with wrong params")
        return value::integer(fclose((parameters[0].pointer.first) cast *void))
    } else if (func_name == "ftell") {
        assert(parameters.size == 1 && is_pointer(parameters[0]), "Calling ftell with wrong params")
        return value::long_int(ftell((parameters[0].pointer.first) cast *void))
    } else if (func_name == "fseek") {
        assert(parameters.size == 3 && is_pointer(parameters[0]) && is_long_int(parameters[1]) && is_integer(parameters[2]), "Calling fseek with wrong params")
        return value::integer(fseek((parameters[0].pointer.first) cast *void, parameters[1].long_int, parameters[2].integer))
    } else if (func_name == "fread") {
        assert(parameters.size == 4 && is_pointer(parameters[0]) && is_ulong_int(parameters[1]) && is_ulong_int(parameters[2]) && is_pointer(parameters[3]), "Calling fread with wrong params")
        return value::ulong_int(fread((parameters[0].pointer.first) cast *void, parameters[1].ulong_int, parameters[2].ulong_int, parameters[3].pointer.first))
    } else if (func_name == "fwrite") {
        assert(parameters.size == 4 && is_pointer(parameters[0]) && is_ulong_int(parameters[1]) && is_ulong_int(parameters[2]) && is_pointer(parameters[3]), "Calling fwrite with wrong params")
        return value::ulong_int(fwrite((parameters[0].pointer.first) cast *void, parameters[1].ulong_int, parameters[2].ulong_int, parameters[3].pointer.first))
    } else if (func_name == "exit") {
        assert(parameters.size == 1 && is_integer(parameters[0]), "Calling exit with wrong params")
        exit(parameters[0].integer)
    } else if (func_name == "atan") {
        assert(parameters.size == 1 && is_double_precision(parameters[0]), "Calling atan with wrong params")
        return value::double_precision(atan(parameters[0].double_precision))
    } else if (func_name == "atan2") {
        assert(parameters.size == 2 && is_double_precision(parameters[0]) && is_double_precision(parameters[1]), "Calling atan2 with wrong params")
        return value::double_precision(atan2(parameters[0].double_precision, parameters[1].double_precision))
    } else if (func_name == "acos") {
        assert(parameters.size == 1 && is_double_precision(parameters[0]), "Calling acos with wrong params")
        return value::double_precision(acos(parameters[0].double_precision))
    } else if (func_name == "asin") {
        assert(parameters.size == 1 && is_double_precision(parameters[0]), "Calling asin with wrong params")
        return value::double_precision(asin(parameters[0].double_precision))
    } else if (func_name == "tan") {
        assert(parameters.size == 1 && is_double_precision(parameters[0]), "Calling tan with wrong params")
        return value::double_precision(tan(parameters[0].double_precision))
    } else if (func_name == "cos") {
        assert(parameters.size == 1 && is_double_precision(parameters[0]), "Calling cos with wrong params")
        return value::double_precision(cos(parameters[0].double_precision))
    } else if (func_name == "sin") {
        assert(parameters.size == 1 && is_double_precision(parameters[0]), "Calling sin with wrong params")
        return value::double_precision(sin(parameters[0].double_precision))
    } else if (func_name == "fgets") {
        assert(parameters.size == 3 && is_pointer(parameters[0]) && is_integer(parameters[1]) && is_pointer(parameters[2]), "Calling fgets with wrong params")
        // first param is *char, so reuse for return
        return value::pointer(make_pair((fgets((parameters[0].pointer.first) cast *char, parameters[1].integer, parameters[2].pointer.first)) cast *void, parameters[0].pointer.second))
    } else if (func_name == "popen") {
        assert(parameters.size == 2 && is_pointer(parameters[0]) && is_pointer(parameters[1]), "Calling popen with wrong params")
        return value::pointer(
            make_pair(popen((parameters[0].pointer.first) cast *char, (parameters[1].pointer.first) cast *char), type_ptr(base_type::void_return(), 1)))
    } else if (func_name == "pclose") {
        assert(parameters.size == 1 && is_pointer(parameters[0]), "Calling pclose with wrong params")
        return value::integer(pclose(parameters[0].pointer.first))
    } else {
        error(str("trying to call invalid func: ") + func_name)
    }
    return value::void_nothing()
}
fun interpret_function(function: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    var possible_closure_map = new<map<*ast_node,value>>()->construct()
    function->function.closed_variables.for_each(fun(v: *ast_node) {
        (*possible_closure_map)[v] = interpret_identifier(v, var_stack, enclosing_object, enclosing_func, globals).first
    })
    return make_pair(value::function(make_pair(function, possible_closure_map)), control_flow::nor())
}
fun interpret_if_statement(if_stmt: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    var_stack->push(map<*ast_node,value>())
    var value_from_inside = make_pair(value::void_nothing(), control_flow::nor())
    if (truthy(interpret(if_stmt->if_statement.condition, var_stack, enclosing_object, enclosing_func, globals).first)) {
        value_from_inside = interpret(if_stmt->if_statement.then_part, var_stack, enclosing_object, enclosing_func, globals)
    } else if (if_stmt->if_statement.else_part) {
        value_from_inside = interpret(if_stmt->if_statement.else_part, var_stack, enclosing_object, enclosing_func, globals)
    }
    pop_and_free(var_stack)
    return value_from_inside
}
fun interpret_while_loop(while_loop: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    var_stack->push(map<*ast_node,value>())
    var value_from_inside = make_pair(value::void_nothing(), control_flow::nor())
    var going = true
    while (going && truthy(interpret(while_loop->while_loop.condition, var_stack, enclosing_object, enclosing_func, globals).first)) {
        value_from_inside = interpret(while_loop->while_loop.statement, var_stack, enclosing_object, enclosing_func, globals)
        if (value_from_inside.second == control_flow::ret() || value_from_inside.second == control_flow::bre())
            going = false
        if (value_from_inside.second == control_flow::bre() || value_from_inside.second == control_flow::con())
            value_from_inside = make_pair(value::void_nothing(), control_flow::nor())
    }
    pop_and_free(var_stack)
    return value_from_inside
}
fun interpret_for_loop(for_loop: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    var_stack->push(map<*ast_node,value>())
    var value_from_inside = make_pair(value::void_nothing(), control_flow::nor())
    var going = true
    if (for_loop->for_loop.init)
        interpret(for_loop->for_loop.init, var_stack, enclosing_object, enclosing_func, globals)
    while (going && (!for_loop->for_loop.condition || truthy(interpret(for_loop->for_loop.condition, var_stack, enclosing_object, enclosing_func, globals).first))) {
        value_from_inside = interpret(for_loop->for_loop.body, var_stack, enclosing_object, enclosing_func, globals)
        if (value_from_inside.second == control_flow::ret() || value_from_inside.second == control_flow::bre())
            going = false
        if (value_from_inside.second == control_flow::bre() || value_from_inside.second == control_flow::con())
            value_from_inside = make_pair(value::void_nothing(), control_flow::nor())

        // only run update if we're not breaking or continuing
        if (going && for_loop->for_loop.update)
            interpret(for_loop->for_loop.update, var_stack, enclosing_object, enclosing_func, globals)
    }
    pop_and_free(var_stack)
    return value_from_inside
}
fun interpret_branching_statement(bstatement: *ast_node): pair<value, control_flow> {
    match (bstatement->branching_statement.b_type) {
        branching_type::break_stmt() return make_pair(value::void_nothing(), control_flow::bre())
        branching_type::continue_stmt() return make_pair(value::void_nothing(), control_flow::con())
    }
    error("bad branch type")
}
fun interpret_code_block(block: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    var_stack->push(map<*ast_node,value>())
    for (var i = 0; i < block->code_block.children.size; i++;) {
        var statement = interpret(block->code_block.children[i], var_stack, enclosing_object, enclosing_func, globals)
        match (statement.second) {
            control_flow::con() {
                pop_and_free(var_stack)
                return make_pair(value::void_nothing(), control_flow::con())
            }
            control_flow::bre() {
                pop_and_free(var_stack)
                return make_pair(value::void_nothing(), control_flow::bre())
            }
            control_flow::ret() {
                pop_and_free(var_stack)
                return statement
            }
        }
        // if nor, continue on
    }
    pop_and_free(var_stack)
    return make_pair(value::void_nothing(), control_flow::nor())
}
fun interpret_return_statement(stmt: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    if (stmt->return_statement.return_value == null<ast_node>())
        return make_pair(value::void_nothing(), control_flow::ret())
    var return_expression = stmt->return_statement.return_value
    var return_type = get_ast_type(return_expression)
    var to_ret.construct(): value
    if (get_ast_type(enclosing_func)->return_type->is_ref) {
        to_ret = interpret(return_expression, var_stack, enclosing_object, enclosing_func, globals).first
        if (!is_variable(to_ret)) {
            print("here is: ")
            print_value(to_ret)
            error("interpreter returning reference is not variable")
        }
    } else {
        to_ret = interpret(return_expression, var_stack, enclosing_object, enclosing_func, globals).first
    }
    return make_pair(to_ret, control_flow::ret())
}
fun interpret_declaration_statement(stmt: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    var ident = stmt->declaration_statement.identifier
    var ident_type = ident->identifier.type
    var_stack->top()[ident] = value::variable(make_pair(malloc(type_size(ident_type)),ident_type))
    // NOTE: store_into_variable takes to in as a ref because it might change it in the special case ref = ptr
    if (stmt->declaration_statement.expression) {
        store_into_variable(var_stack->top()[ident], get_real_value(interpret(stmt->declaration_statement.expression, var_stack, enclosing_object, enclosing_func, globals).first))
    } else if (stmt->declaration_statement.init_method_call) {
        interpret(stmt->declaration_statement.init_method_call, var_stack, enclosing_object, enclosing_func, globals)
    }
    return make_pair(value::void_nothing(), control_flow::nor())
}
fun interpret_assignment_statement(stmt: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    var to = interpret(stmt->assignment_statement.to, var_stack, enclosing_object, enclosing_func, globals).first
    var from = interpret(stmt->assignment_statement.from, var_stack, enclosing_object, enclosing_func, globals).first
    assert(is_variable(to), "assigning into not a variable")
    // always do cast now to make our best effort at assignment (assign into a double from a float, etc)
    // unless it's an object
    var from_real = get_real_value(from)
    // NOTE: store_into_variable takes to in as a ref because it might change it in the special case ref = ptr
    if (is_object_like(from_real) || is_function(from_real))
        store_into_variable(to, from_real)
    else
        store_into_variable(to, cast_value(from_real, to.variable.second))
    return make_pair(value::void_nothing(), control_flow::nor())
}
fun interpret_identifier(ident: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    for (var i = 0; i < var_stack->size(); i++;)
        if (var_stack->from_top(i).contains_key(ident))
            return make_pair(var_stack->from_top(i)[ident], control_flow::nor())
    // check for object member / this
    if (is_object_like(enclosing_object)) {
        if (ident->identifier.name == "this")
            return make_pair(value::pointer(make_pair(enclosing_object.object_like.first, enclosing_object.object_like.second->clone_with_increased_indirection())), control_flow::nor())
        var object_def = enclosing_object.object_like.second->type_def
        for (var i = 0; i < object_def->type_def.variables.size; i++;) {
            if (object_def->type_def.variables[i]->declaration_statement.identifier == ident) {
                var ret_ptr = ((enclosing_object.object_like.first) cast *char + offset_into_struct(enclosing_object.object_like.second, ident)) cast *void
                return make_pair(value::variable(make_pair(ret_ptr, ident->identifier.type)), control_flow::nor())
            }
        }
    }
    // check for global
    if (globals->contains_key(ident))
        return make_pair((*globals)[ident], control_flow::nor())
    println("couldn't find " + get_ast_name(ident) + " in interpret identifier, scope:")
    for (var i = 0; i < var_stack->size(); i++;) {
        println(str("level: ") + i)
        var_stack->from_top(i).for_each(fun(key: *ast_node, v: value) print(get_ast_name(key) + " ");)
        println()
    }
    if (is_object_like(enclosing_object)) {
        println("object scope:")
        var object_def = enclosing_object.object_like.second->type_def
        for (var i = 0; i < object_def->type_def.variables.size; i++;) {
            print(get_ast_name(object_def->type_def.variables[i]->declaration_statement.identifier) + " ")
        }
    } else {
        print("no object scope: ")
        print_value(enclosing_object)
    }
    error(str("Cannot find variable: ") + ident->identifier.name)
}
fun interpret_cast(node: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    return make_pair(cast_value(interpret(node->cast.value, var_stack, enclosing_object, enclosing_func, globals).first, node->cast.to_type), control_flow::nor())
}
fun interpret_compiler_intrinsic(node: *ast_node, var_stack: *stack<map<*ast_node, value>>): pair<value, control_flow> {
    var intrinsic_name = node->compiler_intrinsic.intrinsic
    if (intrinsic_name == "sizeof")
        return make_pair(value::ulong_int(type_size(node->compiler_intrinsic.type_parameters[0])), control_flow::nor())
    error(str("bad intrinsic: ") + intrinsic_name)
}
fun interpret_value(val: *ast_node): pair<value, control_flow>
    return make_pair(wrap_value(val), control_flow::nor())
fun interpret(node: *ast_node, var_stack: *stack<map<*ast_node, value>>, enclosing_object: value, enclosing_func: *ast_node, globals: *map<*ast_node, value>): pair<value, control_flow> {
    if (!node) error("cannot interpret null node!")
    match (*node) {
        ast_node::function_call(backing) return interpret_function_call(node, var_stack, enclosing_object, enclosing_func, globals)
        ast_node::function(backing) return interpret_function(node, var_stack, enclosing_object, enclosing_func, globals)
        ast_node::if_statement(backing) return interpret_if_statement(node, var_stack, enclosing_object, enclosing_func, globals)
        ast_node::while_loop(backing) return interpret_while_loop(node, var_stack, enclosing_object, enclosing_func, globals)
        ast_node::for_loop(backing) return interpret_for_loop(node, var_stack, enclosing_object, enclosing_func, globals)
        ast_node::branching_statement(backing) return interpret_branching_statement(node)
        ast_node::code_block(backing) return interpret_code_block(node, var_stack, enclosing_object, enclosing_func, globals)
        ast_node::return_statement(backing) return interpret_return_statement(node, var_stack, enclosing_object, enclosing_func, globals)
        ast_node::declaration_statement(backing) return interpret_declaration_statement(node, var_stack, enclosing_object, enclosing_func, globals)
        ast_node::assignment_statement(backing) return interpret_assignment_statement(node, var_stack, enclosing_object, enclosing_func, globals)
        ast_node::identifier(backing) return interpret_identifier(node, var_stack, enclosing_object, enclosing_func, globals)
        ast_node::cast(backing) return interpret_cast(node, var_stack, enclosing_object, enclosing_func, globals)
        ast_node::compiler_intrinsic(backing) return interpret_compiler_intrinsic(node, var_stack)
        ast_node::value(backing) return interpret_value(node)
    }
    error(str("Cannot interpret node: ") + get_ast_name(node))
}