in reply to Re^4: The Case for Macros in Perl
in thread The Case for Macros in Perl

Way back, in perl4, there was (from perl.man)

-Idirectory may be used in conjunction with -P to tell the C prep +rocessor where to look for include files. By default /usr/incl +ude and /usr/lib/perl are searched. -P causes your script to be run through the C preprocessor + before compilation by perl. (Since both comments and cpp di +rectives begin with the # character, you should avoid starting +comments with any words recognized by the C preprocessor such +as "if", "else" or "define".)
which was dropped (in favour of source filters, I guess). But hey, you can still run your code through cpp:
#define ADD(x,y) x + y my $r = ADD( getPfromSomewhere(), getQfromSomewhere() ); ... my $s = ADD( geta(), getb() );
# 1 "macro.pl" # 1 "<command-line>" # 1 "/usr/include/stdc-predef.h" 1 3 4 # 30 "/usr/include/stdc-predef.h" 3 4 # 1 "/usr/include/x86_64-linux-gnu/bits/predefs.h" 1 3 4 # 31 "/usr/include/stdc-predef.h" 2 3 4 # 1 "<command-line>" 2 # 1 "macro.pl" my $r = getPfromSomewhere() + getQfromSomewhere(); ... my $s = geta() + getb();

"can you tell me the way to Tipperary?" - "well, I wouldn't start from here..."
;-)

perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'

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Re^6: The Case for Macros in Perl
by BrowserUk (Patriarch) on Sep 15, 2014 at 11:15 UTC
    But hey, you can still run your code through cpp:

    True! But its a little like using a combine-harvester to trim your lawn. With extreme care it could be made to work, but there are lots of logistical problems and the potential for things to go very wrong.


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