how would you make a for loop infinite?

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  1. #1
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    how would you make a for loop infinite?

    thank

  2. #2
    and the Hat of Guessing tabstop's Avatar
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    If you think about it for 0.45 seconds, you'll figure out how to do it.

    It will take a lot longer to figure out why you think you want to.

  3. #3
    Dr Dipshi++ mike_g's Avatar
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    Code:
    for(;;)

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    Registered User Swarvy's Avatar
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    Is there any advantage (I mean in terms of CPU efficiency etc) over doing:
    Code:
    for(;;)
    Over something like:
    Code:
    while(1)

  5. #5
    and the Hat of Guessing tabstop's Avatar
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    Since neither of them require any work, I'm pretty sure they would be exactly the same.

  6. #6
    EOP
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    Quote Originally Posted by tabstop View Post
    Since neither of them require any work, I'm pretty sure they would be exactly the same.
    Sometimes guessing isn't enough.

    Code:
    for(;;);
    0041298E  jmp         main+1Eh (41298Eh) 
    
    while(1);
    00412990  mov         eax,1 
    00412995  test        eax,eax 
    00412997  je          main+2Bh (41299Bh) 
    00412999  jmp         main+20h (412990h)

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    C++ Witch laserlight's Avatar
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    Quote Originally Posted by EOP
    Sometimes guessing isn't enough.
    You probably did not enable optimisations, since modern compilers are smart enough to recognise that while(1) is an infinite loop and avoid evaluating its condition as a trivial optimisation.
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    Algorithm Dissector iMalc's Avatar
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    Another way is to use a do ... while(1), and yet another way is to use that language construct starting with g that I shall not speak of.
    I find that for(;;) is the best though because with certain compilers on high warning levels you can get a warning about a conditional expression being constant with the while's.
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    Banned master5001's Avatar
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    You have to use two of those g statements if you wish to break out of that loop.

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    Jack of many languages Dino's Avatar
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    Code:
    #include <stdio.h> 
    
    int main () { 
    label:	
    	goto label ; 
    	return 0;
    }
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  11. #11
    Banned master5001's Avatar
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    *gasp* He dare speak such treacherous words in the form of example!?

  12. #12
    Jack of many languages Dino's Avatar
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    Is this like Voldemort - aka, he whose name is not spoken?
    Mac and Windows cross platform programmer. Ruby lover.

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    12/20: Mario F.:I never was, am not, and never will be, one to shut up in the face of something I think is fundamentally wrong.

    Amen brother!

  13. #13
    Banned master5001's Avatar
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    iMalc said he would not speak of goto statements by name, so I ran with it. Then your very next post was a goto example. So perhaps we can call you Gotomort?

  14. #14
    and the hat of sweating
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    Quote Originally Posted by iMalc View Post
    I find that for(;;) is the best though because with certain compilers on high warning levels you can get a warning about a conditional expression being constant with the while's.
    It also saves 1 keystroke for those lazy people out there.
    "I am probably the laziest programmer on the planet, a fact with which anyone who has ever seen my code will agree." - esbo, 11/15/2008

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  15. #15
    EOP
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    Quote Originally Posted by master5001 View Post
    *gasp* He dare speak such treacherous words in the form of example!?
    I know it's off topic, but here's an even more unspeakable command:

    COBOL Alter Verb

    We now move on to the early COBOL ALTER verb that probably deserves the award for the worst programming language command.
    http://www.gavilan.edu/csis/language...l#_Toc76036283

    When I learned COBOL in the late 80's I asked my teacher if we may use alter in structured programming - he got almost a heart attack.

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