compiler: add builtins

slige/compiler/middle/ast_lower.ts

@@ -122,8 +122,16 @@ export class FnLowerer {
                 return this.lowerAssignStmt(stmt, k);
             case "expr": {
                 const rval = this.lowerExpr(k.expr);
+
                 // ignore the fuck out of the value
-                void rval;
+                const ty = this.ch.exprTy(k.expr);
+                const local = this.local(ty);
+                this.addStmt({
+                    tag: "assign",
+                    place: { local, proj: [] },
+                    rval,
+                });
+
                 return;
             }
         }
@@ -374,6 +382,29 @@ export class FnLowerer {
             return this.lowerCallExprTupleVariantCtor(expr, kind);
         }
         const args = kind.args.map((arg) => this.lowerExprToOperand(arg));
+
+        const calleeTy = this.ch.exprTy(kind.expr);
+        if (calleeTy.kind.tag !== "fn") {
+            throw new Error();
+        }
+        const builtinAttr = calleeTy.kind.item.attrs
+            .find((attr) => attr.ident.text === "builtin");
+        if (builtinAttr) {
+            if (
+                builtinAttr.args?.length !== 1 ||
+                builtinAttr.args[0].kind.tag !== "path" ||
+                builtinAttr.args[0].kind.path.segments.length !== 1 ||
+                !["Hello"].includes(
+                    builtinAttr.args[0].kind.path.segments[0].ident.text,
+                )
+            ) {
+                return { tag: "error" };
+            }
+            const builtinId =
+                builtinAttr.args[0].kind.path.segments[0].ident.text;
+            return { tag: "builtin", builtinId, args };
+        }
+
         const func = this.lowerExprToOperand(kind.expr);
         return { tag: "call", func, args };
     }

slige/compiler/middle/mir.ts

@@ -86,7 +86,8 @@ export type RVal =
     | { tag: "binary"; binaryType: BinaryType; left: Operand; right: Operand }
     | { tag: "unary"; unaryType: UnaryType; operand: Operand }
     | { tag: "adt"; ty: Ty; fields: Operand[]; variant?: ast.Variant }
-    | { tag: "call"; func: Operand; args: Operand[] };
+    | { tag: "call"; func: Operand; args: Operand[] }
+    | { tag: "builtin"; builtinId: string; args: Operand[] };
 
 export type BinaryType =
     | "add"

slige/compiler/parse/parser.ts

@@ -113,7 +113,6 @@ export class Parser {
             const ident = this.parseIdent();
             let args: Expr[] | undefined = undefined;
             if (this.test("(")) {
-                this.step();
                 args = this.parseDelimitedList(
                     this.parseAttrArg,
                     ")",

slige/compiler/program.slg

@@ -1,15 +1,9 @@
 
-enum S {
+#[builtin(Hello)]
-    A(int),
+fn c_hello() -> int {}
-    B { v: int },
-}
 
 fn main() {
-    let s = S::A(123);
+    c_hello();
-    let r = match s {
-        S::A(v) => { 3 + 2 },
-        S::B { v: v } => { 4 },
-    };
 }
 
 

slige/compiler/stringify/hir.ts

@@ -44,22 +44,25 @@ export class HirStringifyer {
     }
 
     public item(item: ast.Item, d = 0): string {
+        const attrs = item.attrs.map((attr) => `${this.attr(attr)}\n`);
         const ident = item.ident.text;
         const pub = item.pub ? "pub " : "";
         const k = item.kind;
         switch (k.tag) {
             case "error":
-                return "<error>;";
+                return `${attrs}<error>;`;
             case "mod_block":
-                return `${pub}mod ${ident} ${this.block(k.block, d)}`;
+                return `${attrs}${pub}mod ${ident} ${this.block(k.block, d)}`;
             case "mod_file":
-                return `${pub}mod ${ident} {\n${this.file(k.ast!, d + 1)}\n}`;
+                return `${attrs}${pub}mod ${ident} {\n${
+                    this.file(k.ast!, d + 1)
+                }\n}`;
             case "enum":
-                return `enum ${ident}: ${
+                return `${attrs}enum ${ident}: ${
                     this.ty(this.ch.enumItemTy(item, k))
                 };`;
             case "struct":
-                return `struct ${ident}: ${
+                return `${attrs}struct ${ident}: ${
                     this.ty(this.ch.structItemTy(item, k))
                 };`;
             case "fn": {
@@ -70,7 +73,7 @@ export class HirStringifyer {
                 const params = k.params
                     .map((param) => this.pat(param.pat, d))
                     .join(", ");
-                return `${pub}fn ${ident}(${params}) -> ${
+                return `${attrs}${pub}fn ${ident}(${params}) -> ${
                     this.ty(ty.kind.returnTy)
                 } ${this.block(k.body!, d)}`;
             }
@@ -218,6 +221,12 @@ export class HirStringifyer {
             .join("::");
     }
 
+    public attr(attr: ast.Attr): string {
+        return `#[${attr.ident.text}${
+            attr.args && `(${attr.args.map((arg) => this.expr(arg, 1))})` || ""
+        }]`;
+    }
+
     public ty(ty: Ty): string {
         return tyToString(this.ctx, ty);
     }

slige/compiler/stringify/mir.ts

@@ -233,6 +233,10 @@ export class MirFnStringifyer {
                 return `call ${this.operand(rval.func)}(${
                     rval.args.map((arg) => this.operand(arg)).join(", ")
                 })`;
+            case "builtin":
+                return `builtin ${rval.builtinId}(${
+                    rval.args.map((arg) => this.operand(arg)).join(", ")
+                })`;
         }
         exhausted(rval);
     }