From 88497965b3217634336e503067168e97401118a0 Mon Sep 17 00:00:00 2001
From: Tangent Wantwight <tangent128@gmail.com>
Date: Sat, 29 Jul 2023 01:45:55 -0400
Subject: [PATCH] Parse Commands with Peg

---
 notcl.js | 53 +++++++++++++++++------------------------------------
 1 file changed, 17 insertions(+), 36 deletions(-)

diff --git a/notcl.js b/notcl.js
index 95facf5..cc74a75 100644
--- a/notcl.js
+++ b/notcl.js
@@ -26,6 +26,19 @@ var Notcl = (() => {
     ([_, word]) => word
   );
 
+  const CommandTerminator = Peg.Sequence(
+    PreWordWhitespace,
+    Peg.Choose(
+      /** @type {Peg.Pattern<unknown>} */ (Peg.Regex(/[\n;]/y)),
+      Peg.End
+    )
+  );
+
+  const Command = Peg.Map(
+    Peg.Sequence(PreCommand, Peg.AtLeast(0, Word), CommandTerminator),
+    ([_padding, words, _end]) => words
+  );
+
   return {
     /**
      * Parse out a Notcl script into an easier-to-interpret representation.
@@ -39,42 +52,10 @@ var Notcl = (() => {
       // fold line endings
       code = code.replace(/(?<!\\)((\\\\)*)\\\n/g, "$1");
 
-      /* Parse */
-      function nextWord(/* TODO: null/]/" terminator */) {
-        // TODO: handle all kinds of brace/substitution stuff
-        const [word, nextIndex] = Word(code, 0) ?? [null, 0];
-        if (word) {
-          code = code.substring(nextIndex);
-          return word;
-        } else {
-          return null;
-        }
-      }
-
-      function nextCommand(/* TODO: null/]/" terminator */) {
-        const command = /** @type {Notcl.Word[]} */ ([]);
-        while (true) {
-          // Strip whitespace and comments
-          const [preCmd, startIndex] = PreCommand(code, 0) ?? [null, 0];
-          code = code.substring(startIndex);
-          // Strip semicolons
-          if (code[0] == ";") {
-            code = code.substring(1);
-            continue;
-          }
-          break;
-        }
-
-        while (true) {
-          const word = nextWord();
-          if (word) {
-            command.push(word);
-            continue;
-          }
-          break;
-        }
-
-        return command;
+      function nextCommand() {
+        const [words, nextIndex] = Command(code, 0) ?? [[], 0];
+        code = code.substring(nextIndex);
+        return words;
       }
 
       /* Loop through commands, with safety check */