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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 the actions class

The more complex a grammar becomes, the more complex the actions. Almost every rule or token in our current grammar has an action. Even if most of the actions are just one or two lines of code, the fact that the Perl 6 code is mixed with the grammar language makes reading the code difficult. Formatting the code also becomes a difficult task, as you need to add more spaces to indent the code properly. In this section, we will see what Perl 6 offers to tackle this issue.

All actions may be moved to a separate class. Thus, the complete grammar contains a grammar itself and an actions class. Correspondence between the grammar rules and tokens and the actions is achieved by simply giving the same names to the methods of the action class. Let us convert our grammar to use the split approach.

First of all, create a class for actions and pass it to the parser:

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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