Add = for equality and <> for inequality

This will help with people coming from Excel, as well as LLMs generating
formulas based on training data from Excel

Author: jstrieb

TODO.md

@@ -84,7 +84,6 @@
   - Namespaced formula functions
   - Make parsing faster
     - Hand-written recursive descent
-  - Add <> as alternative for !=
 - Local storage
   - Save sheets
   - Load sheets

src/formula.js

@@ -90,6 +90,8 @@ class BinaryOperation extends Expression {
     "<": (x, y) => x < y,
     "&&": (x, y) => x && y,
     "||": (x, y) => x || y,
+    "<>": (x, y) => x !== y,
+    "=": (x, y) => x === y,
 
     // Bitwise
     "&": (x, y) => (x >>> 0) & (y >>> 0),
@@ -458,6 +460,8 @@ const relational = leftAssociativeBinOp(shift, BinaryOperation, [
 const equality = leftAssociativeBinOp(relational, BinaryOperation, [
   "==",
   "!=",
+  "=",
+  "<>",
 ]);
 
 const bitwiseAnd = leftAssociativeBinOp(equality, BinaryOperation, ["&"]);

test/sheet-and-formula.test.js

@@ -178,6 +178,7 @@ test("Complex logical expressions in formulas", async () => {
       "=~0 >>> 0 << 12",
       "=!(~0 >>> 0 & 0x1 | 0xff) || false",
       "=if(5 < 3 || 2 > 1 && 1 == 1 || 2 != 1 && 3 <= 0x5, 2 >= 1, 10)",
+      "=if(5 < 3 || 2 > 1 && 1 = 1 || 2 <> 1 && 3 <= 0x5, 2 >= 1, 10)",
     ],
   ]);
   await expectSheet(state.currentSheet, [
@@ -187,6 +188,7 @@ test("Complex logical expressions in formulas", async () => {
       (~0 >>> 0) << 12,
       !(((~0 >>> 0) & 0x1) | 0xff) || false,
       5 < 3 || (2 > 1 && 1 == 1) || (2 != 1 && 3 <= 0x5) ? 2 >= 1 : 10,
+      5 < 3 || (2 > 1 && 1 == 1) || (2 != 1 && 3 <= 0x5) ? 2 >= 1 : 10,
     ],
   ]);
 });