regexp question: ^ vs \A 1

[whn]

Hi, Experts,

What is the exact difference between ^ & \A?

According to perl books, ^ matches the beginning of a line and \A matches the beginning of a string. Wouldn't they mean the same?

Could someone show me the difference through examples?

In addition, how to use regexp to change the first char of a string into upper case? I know how to do it using substr. But I'd like to know how to do it using regexp.

Many thanks.

 

[feherke]

Hi

A string has a single beginning but it may contain more then on lines, in which case each line has its beginning :

[blue]  DB<1>[/blue] $str="Hello World\nHello Perl Hello Tek-Tips";

[blue]  DB<2>[/blue] print $str=~m/\A(Hello \w+)/gm; # Hello at the beginning of string
Hello World

[blue]  DB<3>[/blue] print $str=~m/^(Hello \w+)/gm; # Hello at the beginning of lines
Hello WorldHello Perl

Additionally this is bad idea :

[blue]  DB<1>[/blue] $str='whn';

[blue]  DB<2>[/blue] $str=~s/(.)/\u\1/;

[blue]  DB<3>[/blue] print $str;
Whn

Better do it like this :

[blue]  DB<1>[/blue] $str='whn';

[blue]  DB<2>[/blue] $str=ucfirst $str;

[blue]  DB<3>[/blue] print $str;
Whn

Feherke.

http://free.rootshell.be/~feherke/

 

[whn]

Thank you so much, Feherke.

Your answer helps a lot.

BTW, I did not know ucfirst before. I suppose there is uclast, too? I am gong to check it now.

Thanks again.