Wot Does this mean?

[thanawala27]

hey can anyoen tell me wot does this mean

$name =~ s/\n.+//g;
$name =~ s/\s+/_/g;
$name =~ s/^_//;
$name =~ s/_$//;
$name =~ s/[^a-zA-Z0-9_]+//g;
$name =~ s/^[0-9_]+//g;


and this one too..
what will be the value of $item in the following cases:

$item = $item . "" . $_;


$item = $item . "," . $Arguments{"cname"}; [ cname is a textbox ]


Any help is apreciated

Thanks,

Ravi

[arne]

Try http://perldoc.perl.org/. The links on the left (esp. Functions, Operators, Special variables) should explain all you need to understand the code you posted :)

[KevinADC]

well, this stuff:

$name =~ s/\n.+//g;
$name =~ s/\s+/_/g;
$name =~ s/^_//;
$name =~ s/_$//;
$name =~ s/[^a-zA-Z0-9_]+//g;
$name =~ s/^[0-9_]+//g;
 

means someone doesn't understand how to write regular expressions very well. The other suff is concatenation, or the joining of strings together to make a new string.

$foo = 'foo';
$bar = 'bar';
$foo = $foo . $bar;
print $foo; [prints "foobar"]

this:

$foo .= $bar; 

is the same as:

$foo = $foo . $bar;

this line shows the coder has limited understanding of the "." operator

$item = $item . "" . $_;

could be written as:

$item .= $_;

[rock7799]

$name =~ s/\n.+//g; this means substitute newline and next all lines with nothing.(g for globaly)

$name =~ s/\s+/_/g; this means substitute mulitple spaces with and underscore.
$name =~ s/^_//; this means substitute word or line starts with(^) underscore to nothing
$name =~ s/_$//; default variable value to nothing
$name =~ s/[^a-zA-Z0-9_]+//g; word with char numbers underscore and following occurance to nothing

$name =~ s/^[0-9_]+//g;
numbers and underscore to nothing

and this one too..
what will be the value of $item in the following cases:

$item = $item . "" . $_; appends default variable to $item


$item = $item . "," . $Arguments{"cname"}; [ cname is a textbox ]

appends comma and a hash value to $item

[KevinADC]

$name =~ s/\n.+//g; this means substitute newline and next all lines with nothing.(g for globaly)

$name =~ s/\s+/_/g; this means substitute mulitple spaces with and underscore.
$name =~ s/^_//; this means substitute word or line starts with(^) underscore to nothing
$name =~ s/_$//; default variable value to nothing
$name =~ s/[^a-zA-Z0-9_]+//g; word with char numbers underscore and following occurance to nothing

$name =~ s/^[0-9_]+//g;
numbers and underscore to nothing

and this one too..
what will be the value of $item in the following cases:

$item = $item . "" . $_; appends default variable to $item


$item = $item . "," . $Arguments{"cname"}; [ cname is a textbox ]

appends comma and a hash value to $item

Some of your explanations are not correct.