feat(unit): numeric evaluation

Author: arnog

src/compute-engine/library/units.ts

@@ -94,8 +94,9 @@ export const UNITS_LIBRARY: SymbolDefinitions = {
 
       return ce._fn('Quantity', [mag, unitArg.canonical]);
     },
-    evaluate: (ops, { engine: ce }) => {
-      return ce._fn('Quantity', [...ops]);
+    evaluate: (ops, { numericApproximation, engine: ce }) => {
+      const mag = numericApproximation ? ops[0].N() : ops[0].evaluate();
+      return ce._fn('Quantity', [mag, ops[1]]);
     },
   },
 

test/playground.ts

@@ -5,6 +5,7 @@ import {
   simplify,
   compile,
   parse,
+  evaluate,
 } from '../src/compute-engine';
 import { expand } from '../src/compute-engine/boxed-expression/expand';
 
@@ -13,6 +14,8 @@ const engine = ce;
 
 console.log(parse('3 \\mathrm{cm} + 5\\mathrm{m}').evaluate().json);
 
+console.log(evaluate('\\frac{123 \\mathrm{J}}{10\\mathrm{m}}').latex);
+
 // 1. sin(theta)**2 + cos(theta)**2 → 1 — Clean trig identity, but too simple.
 // 2. (alpha**2 - beta**2) / (alpha - beta) → didn't simplify. Engine doesn't cancel the
 // difference of squares factoring here.