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Perl

Developed in 1987 by a man named Larry Wall in order to make report processing easier, Perl is a family of programming languages, including most famously Perl 5 and Perl 6. Though it has gone through multiple revisions since its inception, it at heart a general purpose language, able to script for Unix systems at a higher level than C, etc. Some like to think of the name 'Perl' as an acronym -' Practical Extracting and Reporting Language'1, for example - yet it was simply chosen as it is a short word with positive connotations. Perl was almost called Gloria, after Wall's wife, but in the end Wall settled on PEARL, only to find such a language already existed, thus the unique spelling2.

Larry Wall with a big mustache and glasses before a convention

Larry Wall. Image Source: Wikimedia Commons

Though it is not as low-level as the C family, Perl shares much of its structure with it, including its procedural nature. Syntactically, the brace-delimited blocks, control structure, expressions, variables, assignment statements and subroutines of Perl will also be highly familiar to one trained in C, as will the language's capabilities with AWK and sed. One rather unique features of Perl is that its variables must be prefixed with a symbol upon their declaration to show their type. The examples below show scalar and array variable declaration in Perl:

my $scalar_variable;

my @array_variable;

Perl is especially useful in manipulating text files as these high-power text processing facilities allow it to operate past the arbitrary data-length limits many contemporary Unix tools are bound by.

 

References:

1. "perl(1): Practical Extraction/Report Language - Linux man page". Linux.die.net. Retrieved 2013-07-23.

2. Richardson, Marjorie (1999-05-01). "Larry Wall, the Guru of Perl". Linux Journal. Retrieved 2011-01-03.

The camel logo of the icon image was actually chosen by O'Reilley Media for their book Programming Perl but has since become heavily associated with the language and community. 

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