grep to comb, map to alter

Lists example from a Well House Consultants training course
More on Lists [link]

This example is described in the following article(s):
• Fresh Perl Teaching Examples - part 2 of 3 - [link]

Source code: gm Module: P208

=head1 Handling a whole list

You can use Perl lists as much more than containers for
a collection over which you iterate - you can also perform
operations on the list as a whole.

In this example, read from a file handle into a list places
an entire file into a list (each list member being a line of
incoming data) , and then grep is used to filter the list,
and map to tranform each item in the resulting list.

=cut

open (FH,"towns.xyz") or die($!);
@stuff = <FH>;
@local = grep(/ington/,@stuff);
@shout = map(uc,@local);

print @shout;

__END__

Sample output:

Dorothy-2:j10p grahamellis$ perl gm
WASHINGTON
WASHINGTON
WASHINGTON
WASHINGTON
WASHINGTON
ARTHINGTON
TOTTINGTON-(BURY)
CARDINGTON
ALDINGTON
TODDINGTON-(GLOS)
WITHINGTON
GREAT_MOLLINGTON
ECKINGTON-(DERBYS)
KINGTON_LANGLEY
ACCRINGTON
BRIDLINGTON
CHEVINGTON
DALMELLINGTON
CHEDDINGTON
HARTINGTON
TADDINGTON
NONINGTON
DARLINGTON
STUBBINGTON-(HANTS)
HONINGTON
UFFINGTON
LAVINGTON-(WILTS)
BOBBINGTON
WILMINGTON
BLACK_TORRINGTON
EASTRINGTON
TARRINGTON
GREAT_WHITTINGTON
BENINGTON
NUNNINGTON
LOWER_WITHINGTON
HILLINGTON
WATLINGTON
EGLINGTON (WILL START 028)
SOUTH_COCKERINGTON
TODDINGTON-(BEDS)
RUSKINGTON-(LINCS)
HORSINGTON
WHITTINGTON
KINGTON
EAST_ALLINGTON
SYMINGTON-(AYR)
IVINGTON
CALLINGTON
LYMINGTON-(HANTS)
LITTLE_CHERINGTON
CHADLINGTON
ILMINGTON
HADDINGTON
BOLLINGTON
BICKINGTON
CARSINGTON
LONGFRAMLINGTON
HULLAVINGTON
ASHINGTON-(NRTHUMB)
BEDLINGTON
CRAMLINGTON
STANNINGTON
ORPINGTON
DORRINGTON
GRASSINGTON
POCKLINGTON
HIGH_BICKINGTON
DUDDINGTON
EASINGTON
WEST_CHILTINGTON
NEWINGTON
DODDINGTON
TORRINGTON
WELLINGTON
GARSINGTON
KIDLINGTON
BLETCHINGTON
DEDDINGTON
HOLLINGTON
LAMINGTON
WORKINGTON
ASHINGTON-(W_SUSSX)
RUSTINGTON
ELVINGTON-(YORK)
STORRINGTON
STOKE_GOLDINGTON
DINNINGTON
WASHINGTON
WARRINGTON
LEAMINGTON_SPA
WRINGTON
RILLINGTON
HARRINGTON
UPPINGTON
PATRINGTON
DURRINGTON_WALLS
Dorothy-2:j10p grahamellis$

Learn about this subject

This module and example are covered on the following public courses:
* Perl Programming
* Perl bootcamp
* Learning to program in Perl
* Perl Programming
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