retrieving referenced hash information

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

Greetings

I'm trying to find a way to read in the reference names
(unknown names) and find values to specific pattern-
matched names. Can anyone help?

In the example below, I want to know what names are used
for referencing that start with "TH" and their values.
(i.e. THATCODE, THISCODE, etc...)

Example:

$rec = {
    TEXT      => $string,
    SEQUENCE  => [ @old_values ],
    LOOKUP    => { %some_table },
    THATCODE  => \&some_function,
    THISCODE  => sub { $_[0] ** $_[1] },
    HANDLE    => \*STDOUT,
};
[download]

regards
Sacco

Comment on retrieving referenced hash information Download Code

Replies are listed 'Best First'.
Re: retrieving referenced hash information by chip (Curate) on Mar 12, 2004 at 17:41 UTC
`@whatyouwant = grep { /^TH/ } keys %$rec;` -- Chip Salzenberg, Free-Floating Agent of Chaos	[reply] [d/l]
Re: retrieving referenced hash information by DigitalKitty (Parson) on Mar 12, 2004 at 19:30 UTC
In the example below, I want to know what names are used for referencing that start with "TH" and their values. (i.e. THATCODE, THISCODE, etc...) Hi Sacco. `$rec = { TEXT => $string, SEQUENCE => [ @old_values ], LOOKUP => { %some_table }, THATCODE => \&some_function, THISCODE => sub { $_[0] ** $_[1] }, HANDLE => \STDOUT, }; my %hash = %$rec; while ( ( $key, $value ) = each %hash ) { print "$key = $value\n" if( $key =~ /^TH/ ); }` [download] Output: `C:\>perl p14.pl THISCODE = CODE(0x155ad54) THATCODE = CODE(0x155ac40) C:\>` [download] The CODE(address) indicates a subroutine. If you wanted to look for keys that did not* begin with 'TH', you could use the following program: `$rec = { TEXT => $string, SEQUENCE => [ @old_values ], LOOKUP => { %some_table }, THATCODE => \&some_function, THISCODE => sub { $_[0] ** $_[1] }, HANDLE => \*STDOUT, }; my %hash = %$rec; while ( ( $key, $value ) = each %hash ) { print "$key = $value\n" if( $key !~ /^TH/ ); }` [download] Output: `C:\>perl p14.pl TEXT = SEQUENCE = ARRAY(0x15550f0) LOOKUP = HASH(0x15551b0) HANDLE = GLOB(0x155a5c4) C:\>` [download] Hope this helps, -Katie.	[reply] [d/l] [select]