Eric Foster 35b96bc934 initial commit | 6 years ago | |
---|---|---|
.. | ||
LICENSE | 6 years ago | |
README.md | 6 years ago | |
index.js | 6 years ago | |
package.json | 6 years ago | |
unreachableBranchTransformer.js | 6 years ago |
Removes unreachable code branches in if
statements, ternaries ?
, and logical operations ||
&&
, where the test is determinable (like comparing two constants). This is similar to what UglifyJS's "dead_code" compressor option does, but without the extra code transformations.
When combined with something like envify and browserify, you can perform conditional require
calls without including more code than you need.
npm install unreachable-branch-transform
// original
var transport = process.env.TARGET === 'client' ? require('ajax') : require('fs');
// after envify
var transport = 'server' === 'client' ? require('ajax') : require('fs');
// then after unreachable-branch-transform
var transport = require('fs');
// original
if (process.env.NODE_ENV === 'development') {
console.log('in dev mode');
} else {
console.log('in some other mode');
}
// after envify
if ('production' === 'development') {
console.log('in dev mode');
} else {
console.log('in some other mode');
}
// then after unreachable-branch-transform
{
console.log('in some other mode');
}
unreachable-branch-transform
can be used a browserify transform. Just include it like any other transform.unreachable-branch-transform
can also be used on raw code by calling the transform
function exposed by requiring the package.esmangle-evaluator
is from the esmangle project.