Re: gawk: "print" not allowed in PATTERN, only in ACTION?

[Aharon Robbins]

Greetings. Re this:

> From: address@hidden (Dan Jacobson)
> Subject: gawk: "print" not allowed in PATTERN, only in ACTION?
> Date: 02 Jul 2001 16:34:06 +0800
>
> The gawk manual's "print" node  doesn't say why one can't use "print" in the 
> PATTERN portion:
> gawk-3.1.0 '1 && print "wow" && 1{print}'<<!
> mom
> !

That's the definition of the language.

> gawk-3.1.0 '(a=m $1 && (print a > "/dev/stderr")&& a ~ "mom")'<<!
> wwww
> !
>
> An error is triggered at "print".
> Let's say I want to print out some debugging info right then and
> there...

Define a function:

        function debugout(name, val)
        {
                printf("%s = %s\n", name, val) > "/dev/stderr"
                return 1
        }
        (a=(m $1) && debugout("a", a) && a ~ "mom")

Note also that you should parenthesize the string concatenation to make
sure it does what you want.

Hope this helps.

Arnold