AS3: …(rest) parameter
This may look strange at the first sight. Actually this new keyword allows function to accept any number of arguments.
Actionscript:
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function testing(...rest){
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trace(rest);
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}
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testing(1,2,'abc','def') // output: 1,2,abc,def
The arguments need to be separated by comma, and they will be stored into the array named "rest". It is not a must to name it "rest". You can use whatever names, just make sure you do not use other AS keywords.
Actionscript:
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function testing2(...student){
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trace('There are ' + student.length + ' students'); //
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trace('The 1st student is '+ student[0]);
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trace('The 3rd student is '+ student[2]);
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}
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testing2('Peter','Mary','Albert','Joyce');
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/*
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output:
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There are 4 students
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The 1st student is Peter
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The 3rd student is Albert
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*/
You can also use with other predefined parameters, and ...rest need to be the last parameter specified.
Actionscript:
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function myFriends(myName, ...friends){
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trace('My name is ' + myName);
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trace('I have ' + friends.length + ' good friends. They are:');
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for(var i:int in friends){
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trace(friends[i]);
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}
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}
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myFriends('Peter','Mary','Joseph');
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/*
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output:
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My name is Peter
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I have 2 good friends. They are:
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Mary
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Joseph
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*/
...rest is recommended instead of the arguments object. They are very similar, but the new ...rest do not have functionality like arguments.callee.
(maybe I can include that in a tutorial later?)