node.js - About this and self in javascript -


i know "self" magic. @ snippet nodejs(not complete).

socket.prototype.connect = function(options, cb) { ......   var self = this;   var pipe = !!options.path;    if (this.destroyed || !this._handle) {     this._handle = pipe ? createpipe() : createtcp();     initsockethandle(this);   }    if (typeof cb === 'function') {     self.once('connect', cb);   }    timers.active(this);    self._connecting = true;   self.writable = true; ...... }

it understanding must use self create closure. here there no closures in these lines author use both after assigning self. make difference here?

in you've shown in particular code example, there no reason have self variable because there no other function scopes might need access original value of this.

some developers have consistent methodology or convention create local variable self , assign value of this have use, if needed, in closures. self variable can minimized smaller this because can renamed 1 character variable name, this cannot renamed.

in case, functionality here not affected if self removed , this used in particular method.

my own personal convention define self if needed same logic use other local variables , use inside closure needed.


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