20 lines
710 B
ReStructuredText
20 lines
710 B
ReStructuredText
Predicate Language
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==================
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The predicate language allows the user to define simple predicates
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(Boolean-valued functions) that Dune can evaluate. Here is a semiformal
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specification of the predicate language:
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.. productionlist::
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pred : (and `pred` `pred`)
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: (or `pred` `pred`)
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: (not `pred`)
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: :standard
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: `element`
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The exact meaning of ``:standard`` and the nature of :token:`element` depend on
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the context.
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For example, in the case of the :doc:`/reference/dune/subdir`, an
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:token:`element` corresponds to file glob patterns.
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Another example is the user action :doc:`actions/with-accepted-exit-codes`,
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where an :token:`element` corresponds to a literal integer.
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