macro definition inside match bug?

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Ancient One

Joined: 28 Feb 2005
Posts: 55

Ancient One 01 Feb 2006, 05:53

there's a serious bugs in macro definition inside match. i don't know how to describe it, so i give this example. try this

Code:

match , {
 macro a {display 'a'}
 macro b {}
}

no error. try this

Code:

match , {
 macro a {display 'a'}
 macro b {}
 a
}

no error. try this

Code:

match , {
 macro a {display 'a'}
 macro b {}
}
a

this also exist in the last stable release of 1.64.

01 Feb 2006, 05:53

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20341
Location: In your JS exploiting you and your system

revolution 01 Feb 2006, 07:12

Use the backslash to escape the closing curly brackets.

Code:

match , {
macro x{ \}
}

Although there is a minor bug been existing for many previous versions where the preprocessor does not detect mitmatched open and close curly brackets. But it is not serious when the beackslash is used to properly close things.

01 Feb 2006, 07:12

Ancient One

Joined: 28 Feb 2005
Posts: 55

Ancient One 01 Feb 2006, 07:26

using backlash is the correct way to do this, but the above error should be detected, example in code like

Code:

macro a {
 macro b {}
}

fasm detect the error.

01 Feb 2006, 07:26

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8353
Location: Kraków, Poland

Tomasz Grysztar 01 Feb 2006, 14:35

The "{" character is not disallowed inside the macro block - only "}" is treated specially and always means closing the current block (you can find this information in the manual, though it may appear hidden a bit).

Let's look at your second sample (the first one actually causes an error< I guess you did copy not the right one sample there):

Code:

match , {
 macro a {display 'a'}
 macro b {}
 a
}

I'll indent it a bit differently to explain how it works:

Code:

match ,
{
  macro a
  {
    display 'a'
}

    macro b
    {
  }
      a
    }

The "match" begins the definition of "a" macro, but doesn't close it. So the the definition of a macro continues, and contains also "macro b" and "{" character before it is ended with "}". Now the next line invokes the "a" macro - so it begins the definition of "b" macro, but also doesn't close it, and thus the last "}" finally closes the definition of "b" macro - everything is OK.

01 Feb 2006, 14:35

Ancient One

Joined: 28 Feb 2005
Posts: 55

Ancient One 09 Feb 2006, 05:51

oh... now i understand..thanks a lot privalov.

09 Feb 2006, 05:51

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