author | Mahlon E. Smith <mahlon@martini.nu> |
Sat, 22 Jan 2011 01:54:06 -0800 | |
branch | ruby-modules |
changeset 6 | 62a5ac525ce8 |
parent 2 | e5c705047540 |
permissions | -rw-r--r-- |
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9e127bf6e84f
Initial commit of chunker, a ruby module to aid with data blocks.
mahlon
parents:
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Preface: |
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Ruby provides an automatic constant called DATA, which is an IO object |
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that references all text in the current file under an __END__ token. |
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I find it convenient to use the __END__ area to store all sorts of |
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stuff, rather than have to worry about distributing separate files. |
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The problem: |
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The DATA constant is determined from whatever ruby believes $0 to be. |
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It doesn't work inside of other required libraries, so you'll see stuff |
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like this all the time: |
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END = File.open( __FILE__ ).read.split( /^__END__/, 2 ).last |
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It works, but it's more work than I want to do. |
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A workaround: |
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Chunker solves this by parsing __END__ tokens for you, and making it |
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available in the form of a 'DATA_END' constant. It installs this |
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constant into the class that includes Chunker, so you can use it again |
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and again, assuming you use a different file for each class. |
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9e127bf6e84f
Initial commit of chunker, a ruby module to aid with data blocks.
mahlon
parents:
diff
changeset
|
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It also automatically parses out other things that look like tokens, so |
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you can easily have multiple, distinct documents all embedded into the |
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__END__ block. |
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Usage: |
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There is no direct interface to Chunker. Just include it from a |
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class to have that file's __END__ data blocks magically become DATA_* |
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IO constants within that class. |
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Example: |
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This produces the string "Yep.\n". |
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9e127bf6e84f
Initial commit of chunker, a ruby module to aid with data blocks.
mahlon
parents:
diff
changeset
|
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require 'chunker' |
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class Foom |
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include Chunker |
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end |
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puts Foom.new.class.const_get( :DATA_WICKED ).read |
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1
9e127bf6e84f
Initial commit of chunker, a ruby module to aid with data blocks.
mahlon
parents:
diff
changeset
|
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__END__ |
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Stuff in the END block! |
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__WOW__ |
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Ultimate success! |
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__WICKED__ |
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Yep. |
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