Highlight.pl
From Wiki at Neela Nurseries
Contents
Intro
^ highlight.pl usage
Some examples of how to use the Perl text highlight mark-up script . . .
Example 1 - highlight filename, colon field separator in `grep` output and fixed pattern:
$ highlight z ^.[^:]* magenta : cyan 'struct _ns1__PrintLabel' red
^ Useful Perl pattern matches
^ Perl text highlighting mark-up script source
#!/usr/bin/perl -T
# #!/usr/bin/perl
##======================================================================
##
## FILE: highlight-like-grep.pl
##
##
## PURPOSE: to provide simple and quick HTML text highlighting,
## to aid in text based wiki content.
##
##
## NOTES: Started on 2016-12-05 by Ted Havelka.
##
##
##
## REFERENCES:
##
## * https://perlmaven.com/how-to-split-a-text-file-line-by-line
##
## * http://perldoc.perl.org/functions/sprintf.html
##
=for comment
%% a percent sign
%c a character with the given number
%s a string
%d a signed integer, in decimal
%u an unsigned integer, in decimal
%o an unsigned integer, in octal
%x an unsigned integer, in hexadecimal
%e a floating-point number, in scientific notation
%f a floating-point number, in fixed decimal notation
%g a floating-point number, in %e or %f notation
%X like %x, but using upper-case letters
%E like %e, but using an upper-case "E"
%G like %g, but with an upper-case "E" (if applicable)
%b an unsigned integer, in binary
%B like %b, but using an upper-case "B" with the # flag
%p a pointer (outputs the Perl value's address in hexadecimal)
%n special: *stores* the number of characters output so far
into the next argument in the parameter list
%a hexadecimal floating point
%A like %a, but using upper-case letters
%i a synonym for %d
%D a synonym for %ld
%U a synonym for %lu
%O a synonym for %lo
%F a synonym for %f
printf '%2$d %1$d', 12, 34; # prints "34 12"
printf '%3$d %d %1$d', 1, 2, 3; # prints "3 1 1"
printf '<% d>', 12; # prints "< 12>"
printf '<% d>', 0; # prints "< 0>"
printf '<% d>', -12; # prints "<-12>"
printf '<%+d>', 12; # prints "<+12>"
printf '<%+d>', 0; # prints "<+0>"
printf '<%+d>', -12; # prints "<-12>"
printf '<%6s>', 12; # prints "< 12>"
printf '<%-6s>', 12; # prints "<12 >"
printf '<%06s>', 12; # prints "<000012>"
printf '<%#o>', 12; # prints "<014>"
printf '<%#x>', 12; # prints "<0xc>"
printf '<%#X>', 12; # prints "<0XC>"
printf '<%#b>', 12; # prints "<0b1100>"
printf '<%#B>', 12; # prints "<0B1100>"
printf '<%+ d>', 12; # prints "<+12>"
printf '<% +d>', 12; # prints "<+12>"
=cut
##
##
##
##
##
##
##
##
##
##
##
##======================================================================
use strict;
use warnings;
# no warnings;
use 5.008;
## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub usage
{
print "Usage: $0 [filename] [pattern_1] [highlight_color_1] [pattern_2] [highlight_color_2] [...]\n";
print " where filename is name of file to read,\n";
print " and pattern_1 is first pattern to highlight,\n";
print " highlight_color_1 is color to apply to pattern_1 instances,\n";
print " additional patterns and highlight colors optional . . .\n";
}
sub high_light_one_text_pattern
{
##----------------------------------------------------------------------
## * https://perlmaven.com/how-to-split-a-text-file-line-by-line
##----------------------------------------------------------------------
my $caller = shift;
my $filename = shift;
my $pattern_1 = shift;
my $highlight_color_1 = shift;
my $FILE;
my $line;
my $count_of_lines_processed = 0;
my $tag_for_highlight_1_open = "<font color=\"\">";
my $tag_for_highlight_1_close = "</font>";
# - STEP - Bounds checking here on passed values:
## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# if ( length(...
open (FILE, $filename) or print "Could not open file '$filename' $!";
# - STEP - build text highlighting tag, and HTML tag to set font color:
$tag_for_highlight_1_open = "<font color=\"$highlight_color_1\">";
# - STEP - read file and highlight text, line by line:
$line = <FILE>;
# while ( ($line = <FILE>) && (1) )
while ( ($line ) && (1) )
{
$line =~ s/${pattern_1}/${tag_for_highlight_1_open}${pattern_1}${tag_for_highlight_1_close}/g;
# print "$count_of_lines_processed: $line";
printf('%5s: %s', $count_of_lines_processed, $line);
$line = <FILE>;
++$count_of_lines_processed;
}
printf('closing text file \'%s\' . . .', $filename);
close (FILE);
} # end subroutine high_light_one_text_pattern
sub high_light_five_text_patterns
{
##----------------------------------------------------------------------
## * https://perlmaven.com/how-to-split-a-text-file-line-by-line
##----------------------------------------------------------------------
my $caller = shift;
my $filename = shift;
my $pattern_1 = shift;
my $highlight_color_1 = shift;
my $pattern_2 = shift;
my $highlight_color_2 = shift;
my $pattern_3 = shift;
my $highlight_color_3 = shift;
my $pattern_4 = shift;
my $highlight_color_4 = shift;
my $pattern_5 = shift;
my $highlight_color_5 = shift;
my $FILE;
my $line;
my $count_of_lines_processed = 0;
my $tag_for_highlight_1_open = "<font color=\"\">";
my $tag_for_highlight_2_open = "<font color=\"\">";
my $tag_for_highlight_3_open = "<font color=\"\">";
my $tag_for_highlight_4_open = "<font color=\"\">";
my $tag_for_highlight_5_open = "<font color=\"\">";
my $tag_for_highlight_1_close = "</font>";
print "<sub>: about to highlight up to five text patterns in lines of file . . .\n";
print "\n";
# - STEP - Bounds checking here on passed values:
## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# if ( length(...
open (FILE, $filename) or print "Could not open file '$filename' $!";
# - STEP - build text highlighting tag, and HTML tag to set font color:
if ( length($highlight_color_1) > 0 )
{
$tag_for_highlight_1_open = "<font color=\"$highlight_color_1\">";
}
if ( length($highlight_color_2) > 0 )
{
$tag_for_highlight_2_open = "<font color=\"$highlight_color_2\">";
}
if ( length($highlight_color_3) > 0 )
{
$tag_for_highlight_3_open = "<font color=\"$highlight_color_3\">";
}
if ( length($highlight_color_4) > 0 )
{
$tag_for_highlight_4_open = "<font color=\"$highlight_color_4\">";
}
if ( length($highlight_color_5) > 0 )
{
$tag_for_highlight_5_open = "<font color=\"$highlight_color_5\">";
}
my $pattern_5 = shift;
my $highlight_color_5 = shift;
my $FILE;
my $line;
my $count_of_lines_processed = 0;
my $tag_for_highlight_1_open = "<font color=\"\">";
my $tag_for_highlight_2_open = "<font color=\"\">";
my $tag_for_highlight_3_open = "<font color=\"\">";
my $tag_for_highlight_4_open = "<font color=\"\">";
my $tag_for_highlight_5_open = "<font color=\"\">";
my $tag_for_highlight_1_close = "</font>";
print "<sub>: about to highlight up to five text patterns in lines of file . . .\n";
print "\n";
# - STEP - Bounds checking here on passed values:
## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# if ( length(...
open (FILE, $filename) or print "Could not open file '$filename' $!";
# - STEP - build text highlighting tag, and HTML tag to set font color:
if ( length($highlight_color_1) > 0 )
{
$tag_for_highlight_1_open = "<font color=\"$highlight_color_1\">";
}
if ( length($highlight_color_2) > 0 )
{
$tag_for_highlight_2_open = "<font color=\"$highlight_color_2\">";
}
# - STEP - read file and highlight text, line by line:
while ( ($line = <FILE>) && (1) )
{
if ( length($highlight_color_1) > 0 )
{
# $line =~ s/${pattern_1}/${tag_for_highlight_1_open}${pattern_1}${tag_for_highlight_1_close}/g;
$line =~ s/(${pattern_1})/${tag_for_highlight_1_open}$1${tag_for_highlight_1_close}/g;
}
if ( length($highlight_color_2) > 0 )
{
# $line =~ s/${pattern_2}/${tag_for_highlight_2_open}${pattern_2}${tag_for_highlight_1_close}/g;
$line =~ s/(${pattern_2})/${tag_for_highlight_2_open}$1${tag_for_highlight_1_close}/g;
}
if ( length($highlight_color_3) > 0 )
{
# $line =~ s/${pattern_3}/${tag_for_highlight_3_open}${pattern_3}${tag_for_highlight_1_close}/g;
$line =~ s/(${pattern_3})/${tag_for_highlight_3_open}$1${tag_for_highlight_1_close}/g;
}
if ( length($highlight_color_4) > 0 )
{
# $line =~ s/${pattern_4}/${tag_for_highlight_4_open}${pattern_4}${tag_for_highlight_1_close}/g;
$line =~ s/(${pattern_4})/${tag_for_highlight_4_open}$1${tag_for_highlight_1_close}/g;
}
if ( length($highlight_color_5) gt 0 )
{
# $line =~ s/${pattern_5}/${tag_for_highlight_5_open}${pattern_5}${tag_for_highlight_1_close}/g;
$line =~ s/(${pattern_5})/${tag_for_highlight_5_open}$1${tag_for_highlight_1_close}/g;
}
# print "$count_of_lines_processed: $line";
# printf('%5s: %s', $count_of_lines_processed, $line);
printf('%s', $line);
++$count_of_lines_processed
}
print "\n";
printf('<sub>: closing text file \'%s\' . . .\n', $filename);
close (FILE);
} # end subroutine high_light_five_text_patterns
##----------------------------------------------------------------------
## - SECTION - main line code
##----------------------------------------------------------------------
{
my $argc;
my $filename = $ARGV[0];
my $pattern_1_to_highlight = $ARGV[1];
my $highlight_color_1 = $ARGV[2];
my $flag__show_usage = 0;
print "starting,\n";
if ( length($filename) > 0 )
{
print "received filename to parse, filename is '$filename',\n";
}
else
{
print "Warning - received no name of fil to parse!\n";
$flag__show_usage = 1;
}
if ( length($pattern_1_to_highlight) > 0 )
{
print "received first pattern to highlight, it is '$pattern_1_to_highlight'\n";
}
else
{
print "Warning - received no pattern to highlight!\n";
$flag__show_usage = 1;
}
if ( length($highlight_color_1) > 0 )
{
print "received color of first highlight pattern '$highlight_color_1'\n";
}
else
{
print "Warning - received no color for highlight pattern 1!\n";
$flag__show_usage = 1;
}
if ( $flag__show_usage)
{
usage();
}
# - STEP - Check number of command line arguments, and select a highlighting
# routine based on this number:
$argc = @ARGV;
printf("received %d arguments,\n", $argc);
if ( $argc < 4 )
{
print "calling routine to highlight one text pattern . . .\n";
# high_light_one_text_pattern("main", $filename, "CRC", "red");
high_light_one_text_pattern("main", $filename, $ARGV[1], $ARGV[2]);
}
else
{
print "calling routine to highlight between one and five text patterns . . .\n";
high_light_five_text_patterns("main",
$ARGV[0], # the name of text file to read and highlight select text,
$ARGV[1], $ARGV[2], # pattern 1, highlight color 1,
$ARGV[3], $ARGV[4], # pattern 2, highlight color 2,
$ARGV[5], $ARGV[6], # pattern 3, highlight color 3,
$ARGV[7], $ARGV[8], # pattern 4, highlight color 4,
$ARGV[9], $ARGV[10] # pattern 5, highlight color 5,
);
}
print "done.\n\n";
}
# --- EOF ---
^ References
Perl regular expressions . . .
- https://perldoc.perl.org/perlre.html . . . Perl regex at Perldoc dot org
