hello everyone, i had been trying to make a lexical analyzer for c, where all the keywords were to be inputted in a text file keywords. this i stored in an array. but this process is not being automated. the code i wrote is as follows :- 
#!/usr/bin/env perl
@keywd=`cat /home/vikash/maya/keywords`;
@operatr=`cat /home/vikash/maya/operators`;

print "<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
+>";
foreach $keyword (@keywd){print "$keyword";}
print "<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
+>";

print "\nthe total no. of keywords specified in the file are :($#keywd
+)\n";
print "hello $ENV{'USER'}, greetings !!!  you are ";
print "using display $ENV{'DISPLAY'} \n";

$file='/home/vikash/maya/new.c';
print "\n\n:Lexical Analysis Report:\n\n";
print " |->    Input Code File:- $file\n";
print <<"EOF";
\nThe code used in the lexical analysis is :- \n
EOF
print `cat /home/vikash/maya/new.c`;

for($i=0;$i<$#keywd;$i++)
{
print if /\b^int$\b/;

}

__END__

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the keywords file contains:- auto continue enum if short break switch volatile default extern int signed typedef while case do float long sizeof union char double for register static unsigned const else goto return struct void the problem i'm having is that the keywords are not being taken automatically one after the another from this list of keywords............. if i do 
open(INFO,$file);
while(<INFO>){
print if /\bint\b/;
print if /\bfloat\b/;
}
close(INFO)

[download]
everything's fine........ but i don't want to enter all these keywords one by one. what if in future i were to add a new keyword. i would simply like to modify the keywords file not the whole code........

In reply to how to automate the regular expression match from a file? by vikashiiitdm

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