parser stuff

compiler/Lexer.ts

@@ -25,6 +25,16 @@ export class Lexer {
                 this.step();
             }
             switch (value) {
+                case "break":
+                    return this.token("break", pos);
+                case "return":
+                    return this.token("return", pos);
+                case "let":
+                    return this.token("let", pos);
+                case "fn":
+                    return this.token("fn", pos);
+                case "loop":
+                    return this.token("loop", pos);
                 case "if":
                     return this.token("if", pos);
                 case "else":

compiler/Parser.ts

@@ -25,6 +25,14 @@ export class Parser {
 
     private report(msg: string, pos = this.pos()) {
         console.log(`Parser: ${msg} at ${pos.line}:${pos.col}`);
+        class ReportNotAnError extends Error { constructor() { super("ReportNotAnError"); }  }
+        try {
+            throw new ReportNotAnError();
+        } catch (error) {
+            if (!(error instanceof ReportNotAnError))
+                throw error;
+            console.log(error)
+        }
     }
 
     private stmt(kind: StmtKind, pos: Pos): Stmt {
@@ -65,7 +73,7 @@ export class Parser {
 
     private eatSemicolon() {
         if (!this.test(";")) {
-            this.report("expected ';'");
+            this.report(`expected ';', got '${this.currentToken?.type ?? "eof"}'`);
             return;
         }
         this.step();
@@ -285,20 +293,23 @@ export class Parser {
             const subject = this.parsePrefix();
             return this.expr({ type: "unary", unaryType: "not", subject }, pos);
         }
-        ["+", "*", "==", "-", "/", "!=", "<", ">", "<=", ">=", "or", "and"].forEach((binaryType) => {
-            this.parseBinary(binaryType as BinaryType, pos)
-
-        })
+        for (const binaryType of ["+", "*", "==", "-", "/", "!=", "<", ">", "<=", ">=", "or", "and"]) {
+            const subject = this.parseBinary(binaryType as BinaryType, pos)
+            if (subject !== null) {
+                return subject
+            }
+        }
         return this.parsePostfix();
     }
 
-    public parseBinary(binaryType: BinaryType, pos: Pos) {
+    public parseBinary(binaryType: BinaryType, pos: Pos): Expr | null {
         if (this.test(binaryType)) {
             this.step();
             const left = this.parsePrefix();
             const right = this.parsePrefix();
             return this.expr({ type: "binary", binaryType, left, right }, pos);
         }  
+        return null
     }
 
     public parsePostfix(): Expr {

compiler/example-no-types.slg

@@ -1,30 +1,29 @@
 
-
-fn add(a, b) {
-    + a b
+fn sum(a, b) {
+    + a b;
 }
-// 
-// add(2,3); // -> 5
-// 
-// let a = "Hello";
-// 
-// let b = "world";
-// 
-// println(a + " " + b + "!"); // -> "Hello world!"
-// 
-// if a == b {
-//     println("whaaaat");
-// }
-// else {
-//     println(":o");
-// }
-// 
-// loop {
+
+add(2,3); // -> 5
+
+let a = "Hello";
+ 
+let b = "world";
+
+//println(+ (+ a " ") (+ b "!")); // -> "Hello world!"
+
+if == a b {
+    println("whaaaat");
+}
+else {
+    println(":o");
+}
+
+loop {
 //    let i = 0;
 //
-//     if i >= 10 {
+//    if >= i 10 {
 //       break;
 //    }
 //
 //    i = i + 1;
-// }
+}

compiler/main.ts

@@ -5,20 +5,13 @@ import { Parser } from "./Parser.ts";
 const text = await Deno.readTextFile("example.slg");
 
 const lexer = new Lexer(text);
-console.log("type\tindex\tline:col");
-let current = lexer.next();
-while (current) {
-    console.log(
-        `${
-            current.identValue ?? current.type
-        }\t${current.pos.index}\t${current.pos.line}:${current.pos.col}`,
-    );
-    current = lexer.next();
-}
-const pos = lexer.currentPos();
-console.log(`eof\t${pos.index}\t${pos.line}:${pos.col}`);
-//const parser = new Parser(lexer);
-//while (!parser.done()) {
-//    const result = parser.parseExpr();
-//    console.log(result);
-//}
+
+// while (token !== null) {
+//     const value = token.identValue ?? token.intValue ?? token.stringValue ?? "";
+//     console.log(`${token.type}\t${value}`)
+//     token = lexer.next();
+// }
+
+const parser = new Parser(lexer)
+const result = parser.parseStmts()
+console.log(JSON.stringify(result, null, 4))