[New-bugs-announce] [issue25830] _TypeAlias: Discrepancy between docstring and behavior

[flying sheep]

New submission from flying sheep:

_TypeAlias claims in its docstring that “It can be used in instance and subclass checks”, yet promptly contradicts itself if you try it: “Type aliases cannot be used with isinstance().”

it would be useful to either document (and therefore bless) type_impl, or make it actually work with isinstance (probably by delegating to type_impl)

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components: Library (Lib)
messages: 256154
nosy: flying sheep
priority: normal
severity: normal
status: open
title: _TypeAlias: Discrepancy between docstring and behavior
type: behavior
versions: Python 3.5, Python 3.6

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue25830>
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