Append a line with special characters before a string

Mentor_works has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Append a line with special characters before a string by haukex (Archbishop) on Oct 03, 2017 at 08:01 UTC
That doesn't sound like a text file to me, but like an HTML file. HTML is not a line-oriented format. What if the `<body` tag has attributes on the next line? What if the line that contains `<body` has tags immediately following it on the same line, or even the entire HTML file on one line, which is also possible? What I am trying to say is, use a proper parser. Also, why are you not inserting the `<link>` into `<head>`? Anyway, here's an example using Mojo::DOM: `use warnings; use strict; use Mojo::DOM; my $html = q{<html><head><link id="1"/></head><body></body></html>}; my $insert = q{<link id="0"/>}; my $dom = Mojo::DOM->new($html); $dom->find('head')->each(sub { $_->child_nodes->first->prepend($insert) }); print "$dom\n"; __END__ <html><head><link id="0"><link id="1"></head><body></body></html>` [download]	[reply] [d/l] [select]
Re: Append a line with special characters before a string by Corion (Patriarch) on Oct 03, 2017 at 06:20 UTC
The general approach would be to read the file line by line and append the `<link ...>` tag whenever you find `<body ...` in it. To give you more concise help, can you tell us where exactly you are having problems? If you show us the code you've already written, that helps us help you much better. Do you have problems with the general program structure? Are loops and conditional statements a problem for you? Do you have problems finding the `<body` string? Do you have example input data that you think should work with the code you have but doesn't?	[reply] [d/l] [select]