Feat: import work and verify compilation

theme/node_modules/once/README.md

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+# once
+
+Only call a function once.
+
+## usage
+
+```javascript
+var once = require('once')
+
+function load (file, cb) {
+  cb = once(cb)
+  loader.load('file')
+  loader.once('load', cb)
+  loader.once('error', cb)
+}
+```
+
+Or add to the Function.prototype in a responsible way:
+
+```javascript
+// only has to be done once
+require('once').proto()
+
+function load (file, cb) {
+  cb = cb.once()
+  loader.load('file')
+  loader.once('load', cb)
+  loader.once('error', cb)
+}
+```
+
+Ironically, the prototype feature makes this module twice as
+complicated as necessary.
+
+To check whether you function has been called, use `fn.called`. Once the
+function is called for the first time the return value of the original
+function is saved in `fn.value` and subsequent calls will continue to
+return this value.
+
+```javascript
+var once = require('once')
+
+function load (cb) {
+  cb = once(cb)
+  var stream = createStream()
+  stream.once('data', cb)
+  stream.once('end', function () {
+    if (!cb.called) cb(new Error('not found'))
+  })
+}
+```