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Allen Wirfs-Brock (2014-02-20T17:09:53.000Z)

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On Feb 20, 2014, at 8:36 AM, Brendan Eich wrote:

> On Feb 20, 2014, at 8:16 AM, Allen Wirfs-Brock <allen at wirfs-brock.com> wrote:
> 
>> Nope, it means that the length of the argument list is less than two, hence an argument corresponding to 'deleteCount' was not passed.
>> 
>> http://people.mozilla.org/~jorendorff/es6-draft.html#sec-ecmascript-standard-built-in-objects (para 4) says: "Unless otherwise specified in the description of a particular function, if a built-in function or constructor is given fewer arguments than the function is specified to require, the function or constructor shall behave exactly as if it had been given sufficient additional arguments, each such argument being the undefined value."
> 
> Note lack of the words "not" and "present" above,
> 
>> So, "is not present" is how handling of missing arguments is "otherwise specified".
>> 
>> If the algorithm need to simply test for an explicitly or implicitly passed undefined, it would simply say "If argument is undefined, then ..."
>> 
>> I always thought "not present" was sufficiently descriptive, in combination with the missing args default to undefined rule, that it didn't need further definition.
> 
> Why? Those words do not occur in the rule's definition.

That's one of the strengths/weaknesses of pseudo code.  It's not manageable to formally define phrase so you depend upon commonly understood the natural language meaning for a lot of things. 

But, I rule of thumb is that if one person is vocal about being confused then many other also probably are.

Boris should file a bug.

Allen



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domenic at domenicdenicola.com (2014-02-24T21:35:05.717Z)

That's one of the strengths/weaknesses of pseudo code.  It's not manageable to formally define phrase so you depend upon commonly understood the natural language meaning for a lot of things. 

But, I rule of thumb is that if one person is vocal about being confused then many other also probably are.

Boris should file a bug.

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