8e2a892469
As discussed in #880, move defn-alias and defmacro-alias to a contrib module. Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
61 lines
1.3 KiB
ReStructuredText
61 lines
1.3 KiB
ReStructuredText
============
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Alias macros
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============
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.. versionadded:: 0.12
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The alias macro module provides the ``(defn-alias)`` and
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``(defmacro-alias)``, that were in Hy core previously.
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Macros
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======
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.. _defn-alias:
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defn-alias
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------------------------
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The ``defn-alias`` and macro is much like `defn`_,
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with the distinction that instead of defining a function with a single
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name, these can also define aliases. Other than taking a list of
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symbols for function names as the first parameter, ``defn-alias``
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is no different from ``defn``.
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.. code-block:: clj
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=> (defn-alias [main-name alias] []
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... (print "Hello!"))
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=> (main-name)
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"Hello!"
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=> (alias)
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"Hello!"
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.. _defmacro-alias:
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defmacro-alias
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--------------
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``defmacro-alias`` is used to define macros with multiple names
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(aliases). The general format is ``(defmacro-alias [names] [parameters]
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expr)``. It creates multiple macros with the same parameter list and
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body, under the specified list of names.
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The following example defines two macros, both of which allow the user
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to write code in infix notation.
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.. code-block:: clj
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=> (defmacro-alias [infix infi] [code]
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... (quasiquote (
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... (unquote (get code 1))
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... (unquote (get code 0))
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... (unquote (get code 2)))))
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=> (infix (1 + 1))
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2
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=> (infi (1 + 1))
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2
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