23 lines
703 B
ReStructuredText
23 lines
703 B
ReStructuredText
op
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==
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Generic, exception-free return values.
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OP stands for "Operation Result".
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This module contains a generic type that can be used as a return type
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for operations that could fail. It adds additional messages to the result.
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This module improves upon the `options module<https://nim-lang.org/docs/options.html>`_
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in that additional messages can be passed along with the presence or absence of a value.
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Basic Usage
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-----------
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.. code-block:: nim
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proc divide(a, b: int): OP[float] =
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## This could fail
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if b == 0:
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return fail "Cannot divide by zero!"
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else:
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return ok a / b # Wrap the result
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let r = divide(42, 0)
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assert r.isOk == false
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assert r.error == "Cannot divide by zero!" |