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You're reading from  Perl 6 Deep Dive

Product typeBook
Published inSep 2017
Reading LevelIntermediate
PublisherPackt
ISBN-139781787282049
Edition1st Edition
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Andrew Shitov
Andrew Shitov
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Andrew Shitov

Andrew Shitov has been a Perl enthusiast since the end of the 1990s, and is the organizer of over 30 Perl conferences in eight countries. He worked as a developer and CTO in leading web-development companies, such as Art. Lebedev Studio, Booking dotCom, and eBay, and he learned from the "Fathers of the Russian Internet", Artemy Lebedev and Anton Nossik. Andrew has been following the Perl 6 development since its beginning in 2000. He ran a blog dedicated to the language, published a series of articles in the Pragmatic Perl magazine, and gives talks about Perl 6 at various Perl events. In 2017, he published the Perl 6 at a Glance book by DeepText, which was the first book on Perl 6 published after the first stable release of the language specification.
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Using reduction

In the previous section, we were calculating the sum of the numbers between 10 and 15. The program, after some transformations, became equivalent to the following one:

say 10 + (11 + (12 + (13 + (14 + 15))));

Each pair of parentheses here corresponds to the recursive call of the sum function. Calls of the function are replaced here with its implementation. This is one of the consequences of the restriction of the state-less approach. Would the function depend on the program state, it would not be possible to replace the function call with its implementation without knowing the values reflecting the state at different moments.

As parentheses do not change any order of execution here, let's remove them:

say 10 + 11 + 12 + 13 + 14 + 15;

What we see here is a list of all the values between 10 and 15 separated by the + operator. We have already met that in the...

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Perl 6 Deep Dive
Published in: Sep 2017Publisher: PacktISBN-13: 9781787282049

Author (1)

author image
Andrew Shitov

Andrew Shitov has been a Perl enthusiast since the end of the 1990s, and is the organizer of over 30 Perl conferences in eight countries. He worked as a developer and CTO in leading web-development companies, such as Art. Lebedev Studio, Booking dotCom, and eBay, and he learned from the "Fathers of the Russian Internet", Artemy Lebedev and Anton Nossik. Andrew has been following the Perl 6 development since its beginning in 2000. He ran a blog dedicated to the language, published a series of articles in the Pragmatic Perl magazine, and gives talks about Perl 6 at various Perl events. In 2017, he published the Perl 6 at a Glance book by DeepText, which was the first book on Perl 6 published after the first stable release of the language specification.
Read more about Andrew Shitov