59 lines
1.2 KiB
ReStructuredText
59 lines
1.2 KiB
ReStructuredText
==========
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Flow
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==========
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.. versionadded:: 0.10.1
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The ``flow`` macros allow directing the flow of a program with greater ease.
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Macros
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======
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.. _case:
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.. _switch:
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case
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-----
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``case`` allows you to decide based on the value of a variable.
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Usage: `(case variable val1 (body1) val2 (body2) ...)`
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Example:
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.. code-block:: hy
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(require hy.contrib.flow)
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(defn temp-commenter [temp]
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(case temp
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-10 (print "It's freezing. Turn up the thermostat!")
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15 (print "Sounds about average.")
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45 (print "Holy smokes. It's hot in here!")
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(print "I don't even know.")))
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switch
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-----
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``switch`` allows you to run code based on the value of a variable.
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A final extra body allows for a default case.
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Usage: `(switch var (cond1) (body1) (cond2) (body2) ... )`
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Example:
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.. code-block:: hy
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(require hy.contrib.flow)
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(defn temp-commenter [temp]
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(switch temp
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(<= 10.0) (print "Better wear a jacket!")
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(<= 25.0) (print "Brace yourselves. Summer is coming!")
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(<= 30.0) (print "Time to get some ice cream.")
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(print "Sounds like a heat wave")))
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