Re: bin/39002: harmful AWK extension: non-portable escaped character

["Greg A. Woods; Planix, Inc." <woods%planix.ca@localhost>]

On 13-Jul-08, at 4:31 PM, David Holland wrote:

> As far as I can tell what you're claiming is that someone might
> intentionally write "foo\.c" in a string constant, intending to get
> the value "foo.c", instead of writing it in the normal way without the
> backslash.

Exactly, though your example is perhaps pedantic and silly to the  
extreme.

The point is that the language (as defined for this implementation)  
clearly shows that the string constants "f\o\o\.\c" and "foo.c" will  
always compare as identical, eg. with .  Furthermore this makes a  
great deal of sense and is rational behaviour given the context and  
heritage of the language.

$ awk 'BEGIN {s="foo.c"; t = "f\o\o\.\c"; if (s == t) print "EQUAL!";  
printf "'%s'\n", t}'
EQUAL!
foo.c


See P. 40-41 in the AWK book for more about the caveats of using  
strings as REs.

--
                                        Greg A. Woods; Planix, Inc.
                                        <woods%planix.ca@localhost>