rue_compiler/compile/expr/
if_expr.rs

1use log::debug;
2use rue_ast::{AstIfExpr, AstNode};
3use rue_hir::{Hir, Value};
4use rue_types::{Type, TypeId, Union};
5
6use crate::{Compiler, compile_expr};
7
8pub fn compile_if_expr(
9    ctx: &mut Compiler,
10    expr: &AstIfExpr,
11    expected_type: Option<TypeId>,
12) -> Value {
13    let condition = if let Some(condition) = expr.condition() {
14        let value = compile_expr(ctx, &condition, None);
15        ctx.check_condition(condition.syntax(), value.ty);
16        value
17    } else {
18        debug!("Unresolved if condition");
19        ctx.builtins().unresolved.clone()
20    };
21
22    let then_expr = if let Some(then_expr) = expr.then_expr() {
23        if expr.inline().is_some() {
24            // We can't type guard if the branches are eagerly evaluated
25            compile_expr(ctx, &then_expr, expected_type)
26        } else {
27            let index = ctx.push_mappings(condition.then_map.clone());
28            let value = compile_expr(ctx, &then_expr, expected_type);
29            ctx.revert_mappings(index);
30            value
31        }
32    } else {
33        debug!("Unresolved if then expr");
34        ctx.builtins().unresolved.clone()
35    };
36
37    let else_expr = if let Some(else_expr) = expr.else_expr() {
38        if expr.inline().is_some() {
39            // We can't type guard if the branches are eagerly evaluated
40            compile_expr(ctx, &else_expr, expected_type)
41        } else {
42            let index = ctx.push_mappings(condition.else_map.clone());
43            let value = compile_expr(ctx, &else_expr, expected_type);
44            ctx.revert_mappings(index);
45            value
46        }
47    } else {
48        debug!("Unresolved if else expr");
49        ctx.builtins().unresolved.clone()
50    };
51
52    let ty = ctx.alloc_type(Type::Union(Union::new(vec![then_expr.ty, else_expr.ty])));
53    let hir = ctx.alloc_hir(Hir::If(
54        condition.hir,
55        then_expr.hir,
56        else_expr.hir,
57        expr.inline().is_some(),
58    ));
59
60    Value::new(hir, ty)
61}
rue_compiler/compile/expr/if_expr.rs

rue_compiler/compile/expr/
if_expr.rs
