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POHow can I subclass Boolean to change string representation without negative side effects outside of my function?
 

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  1. POHow can I subclass Boolean to change string representation without negative side effects outside of my function?
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    <p>I need to a way to wrap a boolean value such that comparisons are not broken and the string result is different than 'false' or 'true' without altering the global boolean values</p> <pre><code>function TestIt(bool){ if(wrapper(bool) == true) return "it was: " + wrapper(bool) if(wrapper(bool) == false) return "it was: " + wrapper(bool) return "no dice" } </code></pre> <p>e.g.</p> <pre><code>var result; result = TestIt(true); // "it was: True" result = TestIt(false); // "it was: False" </code></pre> <p>The attempts I have written have not been able to achieve all of the conditions below at the same time:</p> <pre><code>var initial = true; var result1; var result2; (function(){ result1 = wrapper(true); result2 = wrapper(true); })() // result1 == result2 // result1 == true // result1.toString() != initial.toString() // initial.toString() == true.toString() // initial.toString() == (new Boolean(true)).toString() </code></pre> <p>Can anyone help me please?</p> <p>I need this (automatic) alternate string conversion so that I can duplicate a string created on a server environment using a different language and match it exactly. </p> <p>~~~~~~</p> <p>Edit</p> <p>~~~~~~</p> <p>I forgot to mention that the trouble I am running into is the Boolean "valueOf" method that is called instead of toString (apparently) for string concatenation. </p> <p>~~~~~~</p> <p>Edit #2</p> <p>~~~~~~ </p> <p>This would also need to work for false. I just left that out for brevity. However, wrapper(false) == false gave me a headache.</p> <p>~~~~~~</p> <p>Edit Final</p> <p>~~~~~~</p> <p>It turns out (in the answers below), that you can't override the default behavior like I wanted if string concatenation is used. I am going to work on using an array to solve my problem and then doing custom conversions when I join it back together. It seems like Javascript requires an oddball approach to a conceptually simple problem. </p> <p>Code Example for command line:</p> <pre><code>function boolish(a){a=new Boolean(a);a.toString=function(){return this.valueOf()?"True":"False"};return a}; boolish(false) == false boolish(true) == true boolish(false) + " or " + boolish(true) [boolish(false) , " or " , boolish(true)].join("~~~~~~~~") </code></pre>
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    1. COAre you saying you expect `wrapper(true)` to evaluate to boolean true when used in your `wrapper(true)==true` statement, but `wrapper(true)` should evaluate to a string "True" if used in a string concatenation? That's not going to work.
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    2. CO@nnnnnn Yes, that is what I want. Wrapper can return a new object or something. It doesn't really matter how it happens... if it happens =). I just can't figure out how to do it. Notice that was wrapper(true)==true and not wrapper(true)===true with 3 equal signs.
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    3. CO@RobG that would not work for string concatenation
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