Fold constants

Option: transforms.foldConstants

What it changes

Replaces pure compile-time constant expressions with equivalent literals or selected branches.

var v = 1 + 2 * 3;
if (true && cond) f();

var v = 7;
if (cond) f();

Run this transform by setting transforms.foldConstants to true:

obfuscate.mjs

const output = obfuscate(source, {
  transforms: {
    foldConstants: true,
  },
})

Open the TypeScript implementation on GitHub.

Review behavior checks and cases this transform leaves alone.

Last modified on August 26, 2026