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Merged
jorenham merged 3 commits into from
Dec 7, 2025
Merged

remove literal generic type parameters of Can* #487

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af26108
remove literal generic type parameters
jorenham Dec 7, 2025
7954ad5
bump to 0.15.0.dev0
jorenham Dec 7, 2025
46d91b1
update docs
jorenham Dec 7, 2025
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74 changes: 15 additions & 59 deletions README.md
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Original file line number Diff line number Diff line change
Expand Up @@ -364,7 +364,7 @@ This is why these `optype` interfaces don't accept generic type arguments.
<td><code>do_int</code></td>
<td><code>DoesInt</code></td>
<td><code>__int__</code></td>
<td><code>CanInt[+R: int = int]</code></td>
<td><code>CanInt</code></td>
</tr>
<tr>
<td><code>bool(_)</code></td>
Expand All @@ -378,72 +378,28 @@ This is why these `optype` interfaces don't accept generic type arguments.
<td><code>do_bytes</code></td>
<td><code>DoesBytes</code></td>
<td><code>__bytes__</code></td>
<td><code>CanBytes[+R: bytes = bytes]</code></td>
<td><code>CanBytes</code></td>
</tr>
<tr>
<td><code>str(_)</code></td>
<td><code>do_str</code></td>
<td><code>DoesStr</code></td>
<td><code>__str__</code></td>
<td><code>CanStr[+R: str = str]</code></td>
</tr>
</table>

> [!NOTE]
> The `Can*` interfaces of the types that can used as `typing.Literal`
> accept an optional type parameter `R`.
> This can be used to indicate a literal return type,
> for surgically precise typing, e.g. `None`, `True`, and `42` are
> instances of `CanBool[Literal[False]]`, `CanInt[Literal[1]]`, and
> `CanStr[Literal['42']]`, respectively.

These formatting methods are allowed to return instances that are a subtype
of the `str` builtin. The same holds for the `__format__` argument.
So if you're a 10x developer that wants to hack Python's f-strings, but only
if your type hints are spot-on; `optype` is you friend.

<table>
<tr>
<th colspan="3" align="center">operator</th>
<th colspan="2" align="center">operand</th>
</tr>
<tr>
<td>expression</td>
<th>function</th>
<th>type</th>
<td>method</td>
<th>type</th>
<td><code>CanStr</code></td>
</tr>
<tr>
<td><code>repr(_)</code></td>
<td><code>do_repr</code></td>
<td><code>DoesRepr</code></td>
<td><code>__repr__</code></td>
<td><code>CanRepr[+R:str = str]</code></td>
<td><code>CanRepr</code></td>
</tr>
<tr>
<td><code>format(_, x)</code></td>
<td><code>do_format</code></td>
<td><code>DoesFormat</code></td>
<td><code>__format__</code></td>
<td><code>CanFormat[-T:str = str, +R:str = str]</code></td>
</tr>
</table>

Additionally, `optype` provides protocols for types with (custom) *hash* or
*index* methods:

<table>
<tr>
<th colspan="3" align="center">operator</th>
<th colspan="2" align="center">operand</th>
</tr>
<tr>
<td>expression</td>
<th>function</th>
<th>type</th>
<td>method</td>
<th>type</th>
<td><code>CanFormat</code></td>
</tr>
<tr>
<td><code>hash(_)</code></td>
Expand All @@ -460,7 +416,7 @@ Additionally, `optype` provides protocols for types with (custom) *hash* or
<td><code>do_index</code></td>
<td><code>DoesIndex</code></td>
<td><code>__index__</code></td>
<td><code>CanIndex[+R: int = int]</code></td>
<td><code>CanIndex</code></td>
</tr>
</table>

Expand Down Expand Up @@ -1434,7 +1390,7 @@ Additionally, there is `optype.CanAIterSelf[R]`, with both the
<td><code>do_len</code></td>
<td><code>DoesLen</code></td>
<td><code>__len__</code></td>
<td><code>CanLen[+R:int=int]</code></td>
<td><code>CanLen</code></td>
</tr>
<tr>
<td>
Expand All @@ -1444,7 +1400,7 @@ Additionally, there is `optype.CanAIterSelf[R]`, with both the
<td><code>do_length_hint</code></td>
<td><code>DoesLengthHint</code></td>
<td><code>__length_hint__</code></td>
<td><code>CanLengthHint[+R:int=int]</code></td>
<td><code>CanLengthHint</code></td>
</tr>
<tr>
<td><code>_[k]</code></td>
Expand Down Expand Up @@ -1491,7 +1447,7 @@ Additionally, there is `optype.CanAIterSelf[R]`, with both the
<td><code>__reversed__</code></td>
<td>
<code>CanReversed[+R]</code>, or<br>
<code>CanSequence[-I, +V, +N=int]</code>
<code>CanSequence[-I, +V]</code>
</td>
</tr>
</table>
Expand Down Expand Up @@ -1526,7 +1482,7 @@ specific and flexible `collections.abc.Sequence[V]`.
<td><code>do_getattr</code></td>
<td><code>DoesGetattr</code></td>
<td><code>__getattr__</code></td>
<td><code>CanGetattr[-K:str=str, +V=object]</code></td>
<td><code>CanGetattr[+V=object]</code></td>
</tr>
<tr>
<td>
Expand All @@ -1536,7 +1492,7 @@ specific and flexible `collections.abc.Sequence[V]`.
<td><code>do_setattr</code></td>
<td><code>DoesSetattr</code></td>
<td><code>__setattr__</code></td>
<td><code>CanSetattr[-K:str=str, -V=object]</code></td>
<td><code>CanSetattr[-V=object]</code></td>
</tr>
<tr>
<td>
Expand All @@ -1546,14 +1502,14 @@ specific and flexible `collections.abc.Sequence[V]`.
<td><code>do_delattr</code></td>
<td><code>DoesDelattr</code></td>
<td><code>__delattr__</code></td>
<td><code>CanDelattr[-K:str=str]</code></td>
<td><code>CanDelattr</code></td>
</tr>
<tr>
<td><code>dir(_)</code></td>
<td><code>do_dir</code></td>
<td><code>DoesDir</code></td>
<td><code>__dir__</code></td>
<td><code>CanDir[+R:CanIter[CanIterSelf[str]]]</code></td>
<td><code>CanDir[+R: Iterable[str]]</code></td>
</tr>
</table>

Expand Down Expand Up @@ -1683,7 +1639,7 @@ Interfaces for [descriptors](https://docs.python.org/3/howto/descriptor.html).
<tr>
<td><code>class T: d = _</code></td>
<td><code>__set_name__</code></td>
<td><code>CanSetName[-T, -N: str = str]</code></td>
<td><code>CanSetName[-T]</code></td>
</tr>
</table>

Expand All @@ -1704,7 +1660,7 @@ Interfaces for emulating buffer types using the [buffer protocol][BP].
<tr>
<td><code>v = memoryview(_)</code></td>
<td><code>__buffer__</code></td>
<td><code>CanBuffer[-T: int = int]</code></td>
<td><code>CanBuffer</code></td>
</tr>
<tr>
<td><code>del v</code></td>
Expand Down
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