rue_compiler/compile/expr/
guard.rs

1use std::collections::HashMap;
2
3use log::debug;
4use rue_ast::{AstGuardExpr, AstNode};
5use rue_hir::{Value, generate_check_hir};
6
7use crate::{Compiler, compile_expr, compile_type};
8
9pub fn compile_guard_expr(ctx: &mut Compiler, guard: &AstGuardExpr) -> Value {
10    let ty = if let Some(ty) = guard.ty() {
11        compile_type(ctx, &ty)
12    } else {
13        debug!("Unresolved guard type");
14        ctx.builtins().unresolved.ty
15    };
16
17    let expr = if let Some(expr) = guard.expr() {
18        compile_expr(ctx, &expr, Some(ty))
19    } else {
20        debug!("Unresolved guard expr");
21        ctx.builtins().unresolved.clone()
22    };
23
24    let constraint = ctx.guard_type(guard.syntax(), expr.ty, ty);
25    let builtins = ctx.builtins().clone();
26    let check_hir = generate_check_hir(ctx, &builtins, constraint.check.simplify(), expr.hir);
27
28    let mut value = Value::new(check_hir, ctx.builtins().types.bool);
29
30    if let Some(reference) = expr.reference {
31        let mut then_map = HashMap::new();
32        let mut symbol_map = HashMap::new();
33        symbol_map.insert(reference.path.clone(), ty);
34        then_map.insert(reference.symbol, symbol_map);
35
36        let mut else_map = HashMap::new();
37        if let Some(else_id) = constraint.else_id {
38            let mut symbol_map = HashMap::new();
39            symbol_map.insert(reference.path.clone(), else_id);
40            else_map.insert(reference.symbol, symbol_map);
41        }
42
43        value = value.with_mappings(then_map, else_map);
44    }
45
46    value
47}