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16 lines
917 B
Plaintext
16 lines
917 B
Plaintext
String eval is often used for dynamic code generation. For instance,
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Moose uses it heavily, to generate inlined versions of accessors
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and constructors, which speeds code up at runtime by a significant
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amount. String eval is not without its issues however - it's
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difficult to control the scope it's used in (which determines which
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variables are in scope inside the eval), and it can be quite slow,
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especially if doing a large number of evals.
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This module attempts to solve both of those problems. It provides
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an eval_closure function, which evals a string in a clean environment,
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other than a fixed list of specified variables. It also caches the
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result of the eval, so that doing repeated evals of the same source,
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even with a different environment, will be much faster (but note
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that the description is part of the string to be evaled, so it must
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also be the same (or non-existent) if caching is to work properly).
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