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Re: Semicolons and the do..while statement

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SAM wrote on 29 aug 2012 in comp.lang.javascript:

> Le 29/08/12 08:56, RobG a écrit :
>> The syntax for the do..while statement (ECMA-262 12.6.1[1]) is:
>>
>>      do /Statement/ while ( /Expression/ );
>>
>> Noting the trailing semicolon, I expected the following to throw an
>> error:
>>
>>      do {} while (false) var x = 3;
> 
> var x = 2;
> do { alert(x) } while (x--) var y = 5;
> alert(y);
> 
> isn't "understood" as loop on do+while ?
> something like :
> 
> var x = 2;
> [ do { alert(x) } while (x--) ] [ var y = 5 ]
> [         instruction 1       ] [  instr. 2 ]
> alert(y);
> 
> that loops on the 'while' to do 'do' before to parse the following, no?
> Why to loose time searching a ; when the 'while' is closed by its ")"

[Testing in Chrome:]

var x=2;
do { alert(x) } while (x--) alert(x);


The do-while statement simply ends with the conditional (x--)

the second alert(x) is the next statement showing -1

=============================

Try for fun:

var x=73;
do ; while (x--) alert(x);

This will start an endless loop btw:

var x=-73;
do ; while (x--) alert(x);


 

-- 
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)

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Re: Semicolons and the do..while statement SAM <stephanemoriaux.NoAdmin@wanadoo.fr.invalid> - 2012-08-29 14:35 +0200
  Re: Semicolons and the do..while statement "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2012-08-29 13:41 +0000
    Re: Semicolons and the do..while statement SAM <stephanemoriaux.NoAdmin@wanadoo.fr.invalid> - 2012-08-29 17:47 +0200
      Re: Semicolons and the do..while statement "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2012-08-29 17:23 +0000

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