How do I insert (not overwrite) into a string?

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question: ⭐ (strings)

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Re: How do I insert, (not overwrite) into a string?⭐ by KM (Priest) on Aug 23, 2000 at 20:06 UTC
Another way to do it: `my $str = "ello"; substr($str,0,0,"H");` [download] Cheers, KM	[reply] [d/l]
Re: How do I insert, (not overwrite) into a string? by Shendal (Hermit) on Aug 23, 2000 at 20:01 UTC
`my($str) = 'ello'; $str = "H$str";` [download]	[reply] [d/l]
Re: How do I insert, (not overwrite) into a string? by KM (Priest) on Aug 23, 2000 at 20:21 UTC
Did a quick benchmark out of curiosity: KM: `substr($_,0,0,"H")` Ovid: `s/^(.*)$/H$1/` Shendal: `$_ .= "H".$_` turnstep: `s/^/H/` `Benchmark: timing 100000 iterations of KM, Ovid, Shendal, turnstep... KM: -1 wallclock secs ( 0.55 usr + 0.00 sys = 0.55 CPU) Ovid: 2 wallclock secs ( 2.20 usr + 0.00 sys = 2.20 CPU) Shendal: 0 wallclock secs ( 0.53 usr + 0.00 sys = 0.53 CPU) turnstep: 1 wallclock secs ( 0.98 usr + 0.00 sys = 0.98 CPU)` [download] Cheers, KM	[reply] [d/l] [select]
Re: How do I insert, (not overwrite) into a string? by turnstep (Parson) on Aug 23, 2000 at 20:08 UTC
Regular expressions can handle this just fine as well: `my $string = "ello"; $string =~ s/^/Henry said H/;` [download]	[reply] [d/l]
Re: How do I insert, (not overwrite) into a string? by Ovid (Cardinal) on Aug 23, 2000 at 20:10 UTC
There are several methods to do this. Shendal has listed one. Here are a couple of others: `# Concatenation my $str = 'ello'; $str = 'H' . $str; # Regex my $str = 'ello'; $str =~ s/^(.*)$/H$1/;` [download] Cheers, Ovid	[reply] [d/l]
Re: How do I insert, (not overwrite) into a string? by davorg (Chancellor) on Aug 23, 2000 at 20:08 UTC
`my $str = 'ello'; my $char = 'H'; print $str, "\n"; substr($str, 0, 0, $char); print $str, "\n";` [download]	[reply] [d/l]
Re: How do I insert, (not overwrite) into a string? by redcloud (Parson) on Aug 24, 2000 at 22:32 UTC
Just to follow-up KM and davorg, note that you can use substr() as an lvalue. It's just syntactic sugar, but I like the taste of it. 8^) `use strict; my $str = "ello"; substr($str,0,0) = "H"; print $str, "\n";` [download]	[reply] [d/l]
Re: How do I insert, (not overwrite) into a string? by mphilip1 (Initiate) on May 26, 2010 at 20:13 UTC
try this sub I wrote: `# sub signature: # insertXintoYatZ( X , Y , Z ) ; sub insertXintoYatZ{ my ( $X , $Y , $Z ) = @_; substr( $Y , $Z , -length($Y) ) = $X ; return $Y; } $s = "The black cat climbed the green tree"; print "s = $s \n"; print 'insert = '.($s = insertXintoYatZ( "tall ", $s , 26 ))."\n"; print " (now, s = '$s' ) \n"; # OUTPUT: # s = The black cat climbed the green tree # insert = 'tall ' # (now, s = 'The black cat climbed the tall green tree' )";` [download]	[reply] [d/l]
Re: Answer: How do I insert, (not overwrite) into a string? by bluescreen (Friar) on May 27, 2010 at 13:02 UTC
try this: `#!/usr/bin/perl use strict; sub insert_x_into_y_at_z { my ( $x, $y, $z) = @_; $y =~s/^(.{$z})/$1$x/; return $y; }` [download]	[reply] [d/l]
Re: How do I insert, (not overwrite) into a string? by Fian (Novice) on Apr 02, 2001 at 20:27 UTC
I know this is kinda long winded but if u wanna insert into a string split the thing into its constituent characters and bung em in an array then u can insert whatever u want wherever u want..... `@bitsOfString = split(//,$yourString);` [download] Slán Fian. Edited by davido: Added code tags.	[reply] [d/l]