2009-02-10 14:41:48 +01:00
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The Digest::TransformPath module implements the TransformPath concept.
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A TransformPath is a complex higher-order key that is designed for use
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with chains of functions that sequentially transform a piece of data.
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2007-09-13 22:10:08 +02:00
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2009-02-10 14:41:48 +01:00
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The concept starts with a sizable chunk of data, for example an image,
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for which we can determine a unique identifier, and for which we can
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cheaply determine if and when the source material has changed. A series
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of resource-intensive transforms might be applied to this original data
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to produce another piece of data. In the image example, we might auto-level,
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crop, scale, rotate, colour-balance and then thumbnail the image. This
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transformed data would be put into a cache. If at some future point
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we wish to obtain the same image, but would preferably like to use the
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cached version, we would have to take the original image, reapply the
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transforms, and then compare to the result the first time around.
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Further documentation is found within the module.
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WWW: http://search.cpan.org/dist/Digest-TransformPath/
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