Haskell Language Modules
Syntax
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module Name where -- export all names declared in this file
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module Name (functionOne, Type (..)) where -- export only functionOne, Type, and Type's constructors
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import Module -- import all of Module's exported names
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import qualified Module as MN -- qualified import
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import Module (justThisFunction) -- import only certain names from a module
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import Module hiding (functionName, Type) -- import all names from a module except functionName and Type
Remarks
Haskell has support for modules:
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a module can export all, or a subset of its member types & functions
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a module can "re-export" names it imported from other modules
On the consumer end of a module, one can:
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import all, or a subset of module members
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hide imports of a particular member or set of members
haskell.org has a great chapter on module definition.
