some improvements to binding context

Author: Va1

README.md

@@ -120,6 +120,7 @@ module.exports = {
 ### Callback replacement
 
 You can specify a callback function to have dynamic replacement values.
+The context of this function will be the context of the loader.
 
 In your `webpack.config.js`:
 

lib/replace.js

@@ -1,6 +1,7 @@
 
 function replace (source, options, context) {
-  const { replace, flags, strict } = options
+  const { flags, strict } = options
+
   let search
   if (options.search instanceof RegExp) {
     // if the `search` type is RegExp, we ignore `flags`
@@ -11,11 +12,18 @@ function replace (source, options, context) {
     search = options.search
   }
 
+  let replace
+  if (typeof options.replace === 'function') {
+    replace = options.replace.bind(context)
+  } else {
+    replace = options.replace
+  }
+
   if (strict && (typeof search === 'undefined' || search === null || typeof replace === 'undefined' || replace === null)) {
     throw new Error('Replace failed (strict mode) : options.search and options.replace are required')
   }
 
-  const newSource = source.replace(search, typeof replace === 'function' ? replace.bind(context) : replace)
+  const newSource = source.replace(search, replace)
 
   if (strict && (newSource === source)) {
     throw new Error('Replace failed (strict mode) : ' + options.search + ' → ' + options.replace)