Thread: function return on right hand side of "="

  1. 08-27-2011 #1
    sed_y
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    function return on right hand side of "="

    i recently came across a code which was like

    Code:
     func1() = 0;
    if the function returns an int, what does this code do. can we have function returning a value and be on the right hand side of "="?
    where would such code be useful?

    thanks
    sedy
  2. 08-27-2011 #2
    manasij7479
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    Quote Originally Posted by sed_y View Post
    i recently came across a code which was like

    Code:
     func1() = 0;
    if the function returns an int, what does this code do. can we have function returning a value and be on the right hand side of "="?
    where would such code be useful?

    thanks
    sedy
    The only such situation I know about is when the function returns a value by reference(but that is in C++)
  3. 08-27-2011 #3
    sed_y
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    Quote Originally Posted by manasij7479 View Post
    The only such situation I know about is when the function returns a value by reference(but that is in C++)
    hi,
    can you elaborate on that?
    sedy
  4. 08-27-2011 #4
    laserlight
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    Quote Originally Posted by sed_y
    can you elaborate on that?
    Before that: are you sure you saw that line of code in a C, not a C++, program?
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way
  5. 08-27-2011 #5
    tabstop
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    C++ is a different language than C. Do you actually want to know about C++, or stick with C?
  6. 08-27-2011 #6
    manasij7479
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    Quote Originally Posted by laserlight View Post
    Before that: are you sure you saw that line of code in a C, not a C++, program?
    What is its meaning in a C context ?
  7. 08-27-2011 #7
    CommonTater
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    Quote Originally Posted by manasij7479 View Post
    What is its meaning in a C context ?
    Syntax error... LValue required.
  8. 08-27-2011 #8
    manasij7479
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    Quote Originally Posted by CommonTater View Post
    Syntax error... LValue required.
    Then he must've seen it in C++ code.

    @sed_y : This might be a useful read.
  9. 08-27-2011 #9
    iMalc
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    It will have been a C++ pure virtual function declaration.
    My homepage
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  10. 08-27-2011 #10
    sed_y
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    hi all,
    It was a C++ code. but i thought,
    C might have it too. thats why i posted it.

    sedy
  11. 08-27-2011 #11
    quzah
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    The closest thing in C would be a function pointer:
    Code:
    void foo( void );
void bar( void );
...
void (*baz)( void ) = foo;

baz();
bar = bar;
baz();
baz = NULL;
    But there is no actual () on the assignments.


    Quzah.
    Hope is the first step on the road to disappointment.
  12. 08-27-2011 #12
    laserlight
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    Quote Originally Posted by iMalc
    It will have been a C++ pure virtual function declaration.
    Possible, but it would then be missing the return type.

    Quote Originally Posted by sed_y
    It was a C++ code. but i thought,
    C might have it too. thats why i posted it.
    Next time declare that this is not C, but you want to know if it is valid in C. Actually, if you wanted an explanation, it would have been better to ask for it in the C++ programming forum, with an additional question of whether it applies to C too.
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way
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