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Bump to 3.9. Datetime, Decorator, Match statement

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Jure Šorn 6 months ago
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  1. 37
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  2. 42
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  3. 10
      parse.js
  4. 4
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37
README.md
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@ -590,7 +590,7 @@ Datetime
```python ```python
# $ pip3 install python-dateutil # $ pip3 install python-dateutil
from datetime import date, time, datetime, timedelta, timezone from datetime import date, time, datetime, timedelta, timezone
from dateutil.tz import tzlocal, gettz
import zoneinfo, dateutil.tz
``` ```
```python ```python
@ -601,7 +601,7 @@ from dateutil.tz import tzlocal, gettz
``` ```
* **Aware `<a>` time and datetime objects have defined timezone, while naive `<n>` don't. If object is naive, it is presumed to be in the system's timezone!** * **Aware `<a>` time and datetime objects have defined timezone, while naive `<n>` don't. If object is naive, it is presumed to be in the system's timezone!**
* **`'fold=1'` means the second pass in case of time jumping back for one hour.** * **`'fold=1'` means the second pass in case of time jumping back for one hour.**
* **Timedelta normalizes arguments to ±days, seconds (< 86 400) and microseconds (< 1M).**
* **Timedelta normalizes arguments to ±days, seconds (< 86 400) and microseconds (< 1M). Its str() method returns `'[±D, ]H:MM:SS[.…]'` and total_seconds() a float of all seconds.**
* **Use `'<D/DT>.weekday()'` to get the day of the week as an int, with Monday being 0.** * **Use `'<D/DT>.weekday()'` to get the day of the week as an int, with Monday being 0.**
### Now ### Now
@ -615,13 +615,13 @@ from dateutil.tz import tzlocal, gettz
```python ```python
<tzinfo> = timezone.utc # London without daylight saving time (DST). <tzinfo> = timezone.utc # London without daylight saving time (DST).
<tzinfo> = timezone(<timedelta>) # Timezone with fixed offset from UTC. <tzinfo> = timezone(<timedelta>) # Timezone with fixed offset from UTC.
<tzinfo> = tzlocal() # Local tz with dynamic offset. Also gettz().
<tzinfo> = gettz('<Continent>/<City>') # 'Continent/City_Name' timezone or None.
<tzinfo> = dateutil.tz.tzlocal() # Local timezone with dynamic offset from UTC.
<tzinfo> = zoneinfo.ZoneInfo('<iana_key>') # 'Continent/City_Name' zone with dynamic offset.
<DTa> = <DT>.astimezone([<tzinfo>]) # Converts DT to the passed or local fixed zone. <DTa> = <DT>.astimezone([<tzinfo>]) # Converts DT to the passed or local fixed zone.
<Ta/DTa> = <T/DT>.replace(tzinfo=<tzinfo>) # Changes object's timezone without conversion. <Ta/DTa> = <T/DT>.replace(tzinfo=<tzinfo>) # Changes object's timezone without conversion.
``` ```
* **Timezones returned by tzlocal(), gettz(), and implicit local timezone of naive objects have offsets that vary through time due to DST and historical changes of the zone's base offset.**
* **Standard library's zoneinfo.ZoneInfo() can be used instead of gettz() on Python 3.9 and later. It requires 'tzdata' package on Windows. It doesn't return local tz if arg. is omitted.**
* **Timezones returned by tzlocal(), ZoneInfo() and implicit local timezone of naive objects have offsets that vary through time due to DST and historical changes of the base offset.**
* **To get zoneinfo module to work on Windows run `'> pip3 install tzdata'`.**
### Encode ### Encode
```python ```python
@ -660,7 +660,7 @@ from dateutil.tz import tzlocal, gettz
<TD> = <DTa> - <DTa> # Ignores jumps if they share tzinfo object. <TD> = <DTa> - <DTa> # Ignores jumps if they share tzinfo object.
<D/DT> = <D/DT> ± <TD> # Returned datetime can fall into missing hour. <D/DT> = <D/DT> ± <TD> # Returned datetime can fall into missing hour.
<TD> = <TD> * <float> # Also: <TD> = abs(<TD>) and <TD> = <TD> ±% <TD>. <TD> = <TD> * <float> # Also: <TD> = abs(<TD>) and <TD> = <TD> ±% <TD>.
<float> = <TD> / <TD> # How many hours/weeks/years are in TD. Also //.
<float> = <TD> / <TD> # E.g. how many hours are in timedelta. Also //.
``` ```
@ -739,7 +739,7 @@ def f(x, y, *, z): ... # f(x=1, y=2, z=3) | f(1, y=2, z=3) | f(1, 2, z=
<list> = [*<coll.> [, ...]] # Or: list(<collection>) [+ ...] <list> = [*<coll.> [, ...]] # Or: list(<collection>) [+ ...]
<tuple> = (*<coll.>, [...]) # Or: tuple(<collection>) [+ ...] <tuple> = (*<coll.>, [...]) # Or: tuple(<collection>) [+ ...]
<set> = {*<coll.> [, ...]} # Or: set(<collection>) [| ...] <set> = {*<coll.> [, ...]} # Or: set(<collection>) [| ...]
<dict> = {**<dict> [, ...]} # Or: <dict> | ... (since 3.9)
<dict> = {**<dict> [, ...]} # Or: <dict> | ...
``` ```
```python ```python
@ -913,21 +913,20 @@ def debug(func):
def add(x, y): def add(x, y):
return x + y return x + y
``` ```
* **Wraps is a helper decorator that copies the metadata of the passed function (func) to the function it is wrapping (out).**
* **Without it, `'add.__name__'` would return `'out'`.**
* **Wraps is a helper decorator that copies the metadata of the passed function (func) to the function it is wrapping (out). Without it, `'add.__name__'` would return `'out'`.**
### LRU Cache
### Cache
**Decorator that caches function's return values. All function's arguments must be hashable.** **Decorator that caches function's return values. All function's arguments must be hashable.**
```python ```python
from functools import lru_cache
from functools import cache
@lru_cache(maxsize=None)
@cache
def fib(n): def fib(n):
return n if n < 2 else fib(n-2) + fib(n-1) return n if n < 2 else fib(n-2) + fib(n-1)
``` ```
* **Default size of the cache is 128 values. Passing `'maxsize=None'` makes it unbounded.**
* **CPython interpreter limits recursion depth to 3000 by default. To increase it use `'sys.setrecursionlimit(<int>)'`.**
* **Potential problem with cache is that it can grow indefinitely. To clear the cache run `'fib.cache_clear()'` or use `'@functools.lru_cache(maxsize=<int>)'` instead.**
* **CPython interpreter limits recursion depth to 3000 by default. To increase it run `'sys.setrecursionlimit(<int>)'`.**
### Parametrized Decorator ### Parametrized Decorator
**A decorator that accepts arguments and returns a normal decorator that accepts a function.** **A decorator that accepts arguments and returns a normal decorator that accepts a function.**
@ -1253,7 +1252,7 @@ True
### Collection ### Collection
* **Only required methods are iter() and len(). Len() should return the number of items.** * **Only required methods are iter() and len(). Len() should return the number of items.**
* **This cheatsheet actually means `'<iterable>'` when it uses `'<collection>'`.** * **This cheatsheet actually means `'<iterable>'` when it uses `'<collection>'`.**
* **I chose not to use the name 'iterable' because it sounds scarier and more vague than 'collection'. The only drawback of this decision is that the reader could think a certain function doesn't accept iterators when it does, since iterators are the only built-in objects that are iterable but are not collections.**
* **I chose not to use the name 'iterable' because it sounds scarier and more vague than 'collection'. The main drawback of this decision is that the reader could think a certain function doesn't accept iterators when it does, since iterators are the only built-in objects that are iterable but are not collections.**
```python ```python
class MyCollection: class MyCollection:
def __init__(self, a): def __init__(self, a):
@ -2201,8 +2200,8 @@ match <object/expression>:
### Patterns ### Patterns
```python ```python
<value_pattern> = 1/'abc'/True/None/math.pi # Matches the literal or a dotted name. <value_pattern> = 1/'abc'/True/None/math.pi # Matches the literal or a dotted name.
<class_pattern> = <type>() # Matches any object of that type.
<wildcard_patt> = _ # Matches any object.
<class_pattern> = <type>() # Matches any object of that type (or ABC).
<wildcard_patt> = _ # Matches any object. Useful in last case.
<capture_patt> = <name> # Matches any object and binds it to name. <capture_patt> = <name> # Matches any object and binds it to name.
<as_pattern> = <pattern> as <name> # Binds match to name. Also <type>(<name>). <as_pattern> = <pattern> as <name> # Binds match to name. Also <type>(<name>).
<or_pattern> = <pattern> | <pattern> [| ...] # Matches any of the patterns. <or_pattern> = <pattern> | <pattern> [| ...] # Matches any of the patterns.
@ -2212,7 +2211,7 @@ match <object/expression>:
``` ```
* **Sequence pattern can also be written as a tuple.** * **Sequence pattern can also be written as a tuple.**
* **Use `'*<name>'` and `'**<name>'` in sequence/mapping patterns to bind remaining items.** * **Use `'*<name>'` and `'**<name>'` in sequence/mapping patterns to bind remaining items.**
* **Sequence pattern must match all items, while mapping pattern does not.**
* **Sequence pattern must match all items of the collection, while mapping pattern does not.**
* **Patterns can be surrounded with brackets to override precedence (`'|'` > `'as'` > `','`).** * **Patterns can be surrounded with brackets to override precedence (`'|'` > `'as'` > `','`).**
* **Built-in types allow a single positional pattern that is matched against the entire object.** * **Built-in types allow a single positional pattern that is matched against the entire object.**
* **All names that are bound in the matching case, as well as variables initialized in its block, are visible after the match statement.** * **All names that are bound in the matching case, as well as variables initialized in its block, are visible after the match statement.**

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@ -54,7 +54,7 @@
<body> <body>
<header> <header>
<aside>October 3, 2024</aside>
<aside>October 4, 2024</aside>
<a href="https://gto76.github.io" rel="author">Jure Šorn</a> <a href="https://gto76.github.io" rel="author">Jure Šorn</a>
</header> </header>
@ -515,7 +515,7 @@ Point(x=<span class="hljs-number">1</span>, y=<span class="hljs-number">2</span>
</code></pre> </code></pre>
<div><h2 id="datetime"><a href="#datetime" name="datetime">#</a>Datetime</h2><p><strong>Provides 'date', 'time', 'datetime' and 'timedelta' classes. All are immutable and hashable.</strong></p><pre><code class="python language-python hljs"><span class="hljs-comment"># $ pip3 install python-dateutil</span> <div><h2 id="datetime"><a href="#datetime" name="datetime">#</a>Datetime</h2><p><strong>Provides 'date', 'time', 'datetime' and 'timedelta' classes. All are immutable and hashable.</strong></p><pre><code class="python language-python hljs"><span class="hljs-comment"># $ pip3 install python-dateutil</span>
<span class="hljs-keyword">from</span> datetime <span class="hljs-keyword">import</span> date, time, datetime, timedelta, timezone <span class="hljs-keyword">from</span> datetime <span class="hljs-keyword">import</span> date, time, datetime, timedelta, timezone
<span class="hljs-keyword">from</span> dateutil.tz <span class="hljs-keyword">import</span> tzlocal, gettz
<span class="hljs-keyword">import</span> zoneinfo, dateutil.tz
</code></pre></div> </code></pre></div>
@ -527,7 +527,7 @@ Point(x=<span class="hljs-number">1</span>, y=<span class="hljs-number">2</span>
<ul> <ul>
<li><strong>Aware <code class="apache hljs"><span class="hljs-section">&lt;a&gt;</span></code> time and datetime objects have defined timezone, while naive <code class="apache hljs"><span class="hljs-section">&lt;n&gt;</span></code> don't. If object is naive, it is presumed to be in the system's timezone!</strong></li> <li><strong>Aware <code class="apache hljs"><span class="hljs-section">&lt;a&gt;</span></code> time and datetime objects have defined timezone, while naive <code class="apache hljs"><span class="hljs-section">&lt;n&gt;</span></code> don't. If object is naive, it is presumed to be in the system's timezone!</strong></li>
<li><strong><code class="python hljs"><span class="hljs-string">'fold=1'</span></code> means the second pass in case of time jumping back for one hour.</strong></li> <li><strong><code class="python hljs"><span class="hljs-string">'fold=1'</span></code> means the second pass in case of time jumping back for one hour.</strong></li>
<li><strong>Timedelta normalizes arguments to ±days, seconds (&lt; 86 400) and microseconds (&lt; 1M).</strong></li>
<li><strong>Timedelta normalizes arguments to ±days, seconds (&lt; 86 400) and microseconds (&lt; 1M). Its str() method returns <code class="python hljs"><span class="hljs-string">'[±D, ]H:MM:SS[.…]'</span></code> and total_seconds() a float of all seconds.</strong></li>
<li><strong>Use <code class="python hljs"><span class="hljs-string">'&lt;D/DT&gt;.weekday()'</span></code> to get the day of the week as an int, with Monday being 0.</strong></li> <li><strong>Use <code class="python hljs"><span class="hljs-string">'&lt;D/DT&gt;.weekday()'</span></code> to get the day of the week as an int, with Monday being 0.</strong></li>
</ul> </ul>
<div><h3 id="now">Now</h3><pre><code class="python language-python hljs">&lt;D/DTn&gt; = D/DT.today() <span class="hljs-comment"># Current local date or naive DT. Also DT.now().</span> <div><h3 id="now">Now</h3><pre><code class="python language-python hljs">&lt;D/DTn&gt; = D/DT.today() <span class="hljs-comment"># Current local date or naive DT. Also DT.now().</span>
@ -539,15 +539,15 @@ Point(x=<span class="hljs-number">1</span>, y=<span class="hljs-number">2</span>
</ul> </ul>
<div><h3 id="timezone">Timezone</h3><pre><code class="python language-python apache hljs">&lt;tzinfo&gt; = timezone.utc <span class="hljs-comment"># London without daylight saving time (DST).</span> <div><h3 id="timezone">Timezone</h3><pre><code class="python language-python apache hljs">&lt;tzinfo&gt; = timezone.utc <span class="hljs-comment"># London without daylight saving time (DST).</span>
&lt;tzinfo&gt; = timezone(&lt;timedelta&gt;) <span class="hljs-comment"># Timezone with fixed offset from UTC.</span> &lt;tzinfo&gt; = timezone(&lt;timedelta&gt;) <span class="hljs-comment"># Timezone with fixed offset from UTC.</span>
&lt;tzinfo&gt; = tzlocal() <span class="hljs-comment"># Local tz with dynamic offset. Also gettz().</span>
&lt;tzinfo&gt; = gettz(<span class="hljs-string">'&lt;Continent&gt;/&lt;City&gt;'</span>) <span class="hljs-comment"># 'Continent/City_Name' timezone or None.</span>
&lt;tzinfo&gt; = dateutil.tz.tzlocal() <span class="hljs-comment"># Local timezone with dynamic offset from UTC.</span>
&lt;tzinfo&gt; = zoneinfo.ZoneInfo(<span class="hljs-string">'&lt;iana_key&gt;'</span>) <span class="hljs-comment"># 'Continent/City_Name' zone with dynamic offset.</span>
&lt;DTa&gt; = &lt;DT&gt;.astimezone([&lt;tzinfo&gt;]) <span class="hljs-comment"># Converts DT to the passed or local fixed zone.</span> &lt;DTa&gt; = &lt;DT&gt;.astimezone([&lt;tzinfo&gt;]) <span class="hljs-comment"># Converts DT to the passed or local fixed zone.</span>
&lt;Ta/DTa&gt; = &lt;T/DT&gt;.replace(tzinfo=&lt;tzinfo&gt;) <span class="hljs-comment"># Changes object's timezone without conversion.</span> &lt;Ta/DTa&gt; = &lt;T/DT&gt;.replace(tzinfo=&lt;tzinfo&gt;) <span class="hljs-comment"># Changes object's timezone without conversion.</span>
</code></pre></div> </code></pre></div>
<ul> <ul>
<li><strong>Timezones returned by tzlocal(), gettz(), and implicit local timezone of naive objects have offsets that vary through time due to DST and historical changes of the zone's base offset.</strong></li>
<li><strong>Standard library's zoneinfo.ZoneInfo() can be used instead of gettz() on Python 3.9 and later. It requires 'tzdata' package on Windows. It doesn't return local tz if arg. is omitted.</strong></li>
<li><strong>Timezones returned by tzlocal(), ZoneInfo() and implicit local timezone of naive objects have offsets that vary through time due to DST and historical changes of the base offset.</strong></li>
<li><strong>To get zoneinfo module to work on Windows run <code class="python hljs"><span class="hljs-string">'&gt; pip3 install tzdata'</span></code>.</strong></li>
</ul> </ul>
<div><h3 id="encode">Encode</h3><pre><code class="python language-python apache hljs">&lt;D/T/DT&gt; = D/T/DT.fromisoformat(&lt;str&gt;) <span class="hljs-comment"># Object from ISO string. Raises ValueError.</span> <div><h3 id="encode">Encode</h3><pre><code class="python language-python apache hljs">&lt;D/T/DT&gt; = D/T/DT.fromisoformat(&lt;str&gt;) <span class="hljs-comment"># Object from ISO string. Raises ValueError.</span>
&lt;DT&gt; = DT.strptime(&lt;str&gt;, <span class="hljs-string">'&lt;format&gt;'</span>) <span class="hljs-comment"># Datetime from str, according to format.</span> &lt;DT&gt; = DT.strptime(&lt;str&gt;, <span class="hljs-string">'&lt;format&gt;'</span>) <span class="hljs-comment"># Datetime from str, according to format.</span>
@ -582,7 +582,7 @@ Point(x=<span class="hljs-number">1</span>, y=<span class="hljs-number">2</span>
&lt;TD&gt; = &lt;DTa&gt; - &lt;DTa&gt; <span class="hljs-comment"># Ignores jumps if they share tzinfo object.</span> &lt;TD&gt; = &lt;DTa&gt; - &lt;DTa&gt; <span class="hljs-comment"># Ignores jumps if they share tzinfo object.</span>
&lt;D/DT&gt; = &lt;D/DT&gt; ± &lt;TD&gt; <span class="hljs-comment"># Returned datetime can fall into missing hour.</span> &lt;D/DT&gt; = &lt;D/DT&gt; ± &lt;TD&gt; <span class="hljs-comment"># Returned datetime can fall into missing hour.</span>
&lt;TD&gt; = &lt;TD&gt; * &lt;float&gt; <span class="hljs-comment"># Also: &lt;TD&gt; = abs(&lt;TD&gt;) and &lt;TD&gt; = &lt;TD&gt; ±% &lt;TD&gt;.</span> &lt;TD&gt; = &lt;TD&gt; * &lt;float&gt; <span class="hljs-comment"># Also: &lt;TD&gt; = abs(&lt;TD&gt;) and &lt;TD&gt; = &lt;TD&gt; ±% &lt;TD&gt;.</span>
&lt;float&gt; = &lt;TD&gt; / &lt;TD&gt; <span class="hljs-comment"># How many hours/weeks/years are in TD. Also //.</span>
&lt;float&gt; = &lt;TD&gt; / &lt;TD&gt; <span class="hljs-comment"># E.g. how many hours are in timedelta. Also //.</span>
</code></pre></div> </code></pre></div>
<div><h2 id="arguments"><a href="#arguments" name="arguments">#</a>Arguments</h2><div><h3 id="insidefunctioncall">Inside Function Call</h3><pre><code class="python language-python hljs">func(&lt;positional_args&gt;) <span class="hljs-comment"># func(0, 0)</span> <div><h2 id="arguments"><a href="#arguments" name="arguments">#</a>Arguments</h2><div><h3 id="insidefunctioncall">Inside Function Call</h3><pre><code class="python language-python hljs">func(&lt;positional_args&gt;) <span class="hljs-comment"># func(0, 0)</span>
@ -637,7 +637,7 @@ func(*args, **kwargs)
<div><h3 id="otheruses">Other Uses</h3><pre><code class="python language-python hljs">&lt;list&gt; = [*&lt;coll.&gt; [, ...]] <span class="hljs-comment"># Or: list(&lt;collection&gt;) [+ ...]</span> <div><h3 id="otheruses">Other Uses</h3><pre><code class="python language-python hljs">&lt;list&gt; = [*&lt;coll.&gt; [, ...]] <span class="hljs-comment"># Or: list(&lt;collection&gt;) [+ ...]</span>
&lt;tuple&gt; = (*&lt;coll.&gt;, [...]) <span class="hljs-comment"># Or: tuple(&lt;collection&gt;) [+ ...]</span> &lt;tuple&gt; = (*&lt;coll.&gt;, [...]) <span class="hljs-comment"># Or: tuple(&lt;collection&gt;) [+ ...]</span>
&lt;set&gt; = {*&lt;coll.&gt; [, ...]} <span class="hljs-comment"># Or: set(&lt;collection&gt;) [| ...]</span> &lt;set&gt; = {*&lt;coll.&gt; [, ...]} <span class="hljs-comment"># Or: set(&lt;collection&gt;) [| ...]</span>
&lt;dict&gt; = {**&lt;dict&gt; [, ...]} <span class="hljs-comment"># Or: &lt;dict&gt; | ... (since 3.9)</span>
&lt;dict&gt; = {**&lt;dict&gt; [, ...]} <span class="hljs-comment"># Or: &lt;dict&gt; | ...</span>
</code></pre></div> </code></pre></div>
<pre><code class="python language-python hljs">head, *body, tail = &lt;coll.&gt; <span class="hljs-comment"># Head or tail can be omitted.</span> <pre><code class="python language-python hljs">head, *body, tail = &lt;coll.&gt; <span class="hljs-comment"># Head or tail can be omitted.</span>
@ -766,20 +766,18 @@ player = Player(point, direction) <span class="hljs-comment">#
<ul> <ul>
<li><strong>Wraps is a helper decorator that copies the metadata of the passed function (func) to the function it is wrapping (out).</strong></li>
<li><strong>Without it, <code class="python hljs"><span class="hljs-string">'add.__name__'</span></code> would return <code class="python hljs"><span class="hljs-string">'out'</span></code>.</strong></li>
<li><strong>Wraps is a helper decorator that copies the metadata of the passed function (func) to the function it is wrapping (out). Without it, <code class="python hljs"><span class="hljs-string">'add.__name__'</span></code> would return <code class="python hljs"><span class="hljs-string">'out'</span></code>.</strong></li>
</ul> </ul>
<div><h3 id="lrucache">LRU Cache</h3><p><strong>Decorator that caches function's return values. All function's arguments must be hashable.</strong></p><pre><code class="python language-python hljs"><span class="hljs-keyword">from</span> functools <span class="hljs-keyword">import</span> lru_cache
<div><h3 id="cache">Cache</h3><p><strong>Decorator that caches function's return values. All function's arguments must be hashable.</strong></p><pre><code class="python language-python hljs"><span class="hljs-keyword">from</span> functools <span class="hljs-keyword">import</span> cache
<span class="hljs-meta">@lru_cache(maxsize=None)</span>
<span class="hljs-meta">@cache</span>
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">fib</span><span class="hljs-params">(n)</span>:</span> <span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">fib</span><span class="hljs-params">(n)</span>:</span>
<span class="hljs-keyword">return</span> n <span class="hljs-keyword">if</span> n &lt; <span class="hljs-number">2</span> <span class="hljs-keyword">else</span> fib(n-<span class="hljs-number">2</span>) + fib(n-<span class="hljs-number">1</span>)
</code></pre></div>
<span class="hljs-keyword">return</span> n <span class="hljs-keyword">if</span> n &lt; <span class="hljs-number">2</span> <span class="hljs-keyword">else</span> fib(n-<span class="hljs-number">2</span>) + fib(n-<span class="hljs-number">1</span>)</code></pre></div>
<ul> <ul>
<li><strong>Default size of the cache is 128 values. Passing <code class="python hljs"><span class="hljs-string">'maxsize=None'</span></code> makes it unbounded.</strong></li>
<li><strong>CPython interpreter limits recursion depth to 3000 by default. To increase it use <code class="python hljs"><span class="hljs-string">'sys.setrecursionlimit(&lt;int&gt;)'</span></code>.</strong></li>
<li><strong>Potential problem with cache is that it can grow indefinitely. To clear the cache run <code class="python hljs"><span class="hljs-string">'fib.cache_clear()'</span></code> or use <code class="python hljs"><span class="hljs-string">'@functools.lru_cache(maxsize=&lt;int&gt;)'</span></code> instead.</strong></li>
<li><strong>CPython interpreter limits recursion depth to 3000 by default. To increase it run <code class="python hljs"><span class="hljs-string">'sys.setrecursionlimit(&lt;int&gt;)'</span></code>.</strong></li>
</ul> </ul>
<div><h3 id="parametrizeddecorator">Parametrized Decorator</h3><p><strong>A decorator that accepts arguments and returns a normal decorator that accepts a function.</strong></p><pre><code class="python language-python hljs"><span class="hljs-keyword">from</span> functools <span class="hljs-keyword">import</span> wraps <div><h3 id="parametrizeddecorator">Parametrized Decorator</h3><p><strong>A decorator that accepts arguments and returns a normal decorator that accepts a function.</strong></p><pre><code class="python language-python hljs"><span class="hljs-keyword">from</span> functools <span class="hljs-keyword">import</span> wraps
@ -1063,7 +1061,7 @@ Hello World!
<div><h3 id="collection">Collection</h3><ul> <div><h3 id="collection">Collection</h3><ul>
<li><strong>Only required methods are iter() and len(). Len() should return the number of items.</strong></li> <li><strong>Only required methods are iter() and len(). Len() should return the number of items.</strong></li>
<li><strong>This cheatsheet actually means <code class="python hljs"><span class="hljs-string">'&lt;iterable&gt;'</span></code> when it uses <code class="python hljs"><span class="hljs-string">'&lt;collection&gt;'</span></code>.</strong></li> <li><strong>This cheatsheet actually means <code class="python hljs"><span class="hljs-string">'&lt;iterable&gt;'</span></code> when it uses <code class="python hljs"><span class="hljs-string">'&lt;collection&gt;'</span></code>.</strong></li>
<li><strong>I chose not to use the name 'iterable' because it sounds scarier and more vague than 'collection'. The only drawback of this decision is that the reader could think a certain function doesn't accept iterators when it does, since iterators are the only built-in objects that are iterable but are not collections.</strong></li>
<li><strong>I chose not to use the name 'iterable' because it sounds scarier and more vague than 'collection'. The main drawback of this decision is that the reader could think a certain function doesn't accept iterators when it does, since iterators are the only built-in objects that are iterable but are not collections.</strong></li>
</ul><pre><code class="python language-python hljs"><span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">MyCollection</span>:</span> </ul><pre><code class="python language-python hljs"><span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">MyCollection</span>:</span>
<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">__init__</span><span class="hljs-params">(self, a)</span>:</span> <span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">__init__</span><span class="hljs-params">(self, a)</span>:</span>
self.a = a self.a = a
@ -1805,8 +1803,8 @@ first_element = op.methodcaller(<span class="hljs-string">'pop'</span>, <span
<div><h3 id="patterns">Patterns</h3><pre><code class="python language-python hljs">&lt;value_pattern&gt; = <span class="hljs-number">1</span>/<span class="hljs-string">'abc'</span>/<span class="hljs-keyword">True</span>/<span class="hljs-keyword">None</span>/math.pi <span class="hljs-comment"># Matches the literal or a dotted name.</span> <div><h3 id="patterns">Patterns</h3><pre><code class="python language-python hljs">&lt;value_pattern&gt; = <span class="hljs-number">1</span>/<span class="hljs-string">'abc'</span>/<span class="hljs-keyword">True</span>/<span class="hljs-keyword">None</span>/math.pi <span class="hljs-comment"># Matches the literal or a dotted name.</span>
&lt;class_pattern&gt; = &lt;type&gt;() <span class="hljs-comment"># Matches any object of that type.</span>
&lt;wildcard_patt&gt; = _ <span class="hljs-comment"># Matches any object.</span>
&lt;class_pattern&gt; = &lt;type&gt;() <span class="hljs-comment"># Matches any object of that type (or ABC).</span>
&lt;wildcard_patt&gt; = _ <span class="hljs-comment"># Matches any object. Useful in last case.</span>
&lt;capture_patt&gt; = &lt;name&gt; <span class="hljs-comment"># Matches any object and binds it to name.</span> &lt;capture_patt&gt; = &lt;name&gt; <span class="hljs-comment"># Matches any object and binds it to name.</span>
&lt;as_pattern&gt; = &lt;pattern&gt; <span class="hljs-keyword">as</span> &lt;name&gt; <span class="hljs-comment"># Binds match to name. Also &lt;type&gt;(&lt;name&gt;).</span> &lt;as_pattern&gt; = &lt;pattern&gt; <span class="hljs-keyword">as</span> &lt;name&gt; <span class="hljs-comment"># Binds match to name. Also &lt;type&gt;(&lt;name&gt;).</span>
&lt;or_pattern&gt; = &lt;pattern&gt; | &lt;pattern&gt; [| ...] <span class="hljs-comment"># Matches any of the patterns.</span> &lt;or_pattern&gt; = &lt;pattern&gt; | &lt;pattern&gt; [| ...] <span class="hljs-comment"># Matches any of the patterns.</span>
@ -1818,7 +1816,7 @@ first_element = op.methodcaller(<span class="hljs-string">'pop'</span>, <span
<ul> <ul>
<li><strong>Sequence pattern can also be written as a tuple.</strong></li> <li><strong>Sequence pattern can also be written as a tuple.</strong></li>
<li><strong>Use <code class="python hljs"><span class="hljs-string">'*&lt;name&gt;'</span></code> and <code class="python hljs"><span class="hljs-string">'**&lt;name&gt;'</span></code> in sequence/mapping patterns to bind remaining items.</strong></li> <li><strong>Use <code class="python hljs"><span class="hljs-string">'*&lt;name&gt;'</span></code> and <code class="python hljs"><span class="hljs-string">'**&lt;name&gt;'</span></code> in sequence/mapping patterns to bind remaining items.</strong></li>
<li><strong>Sequence pattern must match all items, while mapping pattern does not.</strong></li>
<li><strong>Sequence pattern must match all items of the collection, while mapping pattern does not.</strong></li>
<li><strong>Patterns can be surrounded with brackets to override precedence (<code class="python hljs"><span class="hljs-string">'|'</span></code> &gt; <code class="python hljs"><span class="hljs-string">'as'</span></code> &gt; <code class="python hljs"><span class="hljs-string">','</span></code>).</strong></li> <li><strong>Patterns can be surrounded with brackets to override precedence (<code class="python hljs"><span class="hljs-string">'|'</span></code> &gt; <code class="python hljs"><span class="hljs-string">'as'</span></code> &gt; <code class="python hljs"><span class="hljs-string">','</span></code>).</strong></li>
<li><strong>Built-in types allow a single positional pattern that is matched against the entire object.</strong></li> <li><strong>Built-in types allow a single positional pattern that is matched against the entire object.</strong></li>
<li><strong>All names that are bound in the matching case, as well as variables initialized in its block, are visible after the match statement.</strong></li> <li><strong>All names that are bound in the matching case, as well as variables initialized in its block, are visible after the match statement.</strong></li>
@ -2931,7 +2929,7 @@ $ deactivate <span class="hljs-comment"># Deactivates the active
<footer> <footer>
<aside>October 3, 2024</aside>
<aside>October 4, 2024</aside>
<a href="https://gto76.github.io" rel="author">Jure Šorn</a> <a href="https://gto76.github.io" rel="author">Jure Šorn</a>
</footer> </footer>

10
parse.js
View File

@ -50,12 +50,12 @@ const BIN_HEX =
'&lt;int&gt; = int(<span class="hljs-string">\'±0b&lt;bin&gt;\'</span>, <span class="hljs-number">0</span>) <span class="hljs-comment"># Or: int(\'±0x&lt;hex&gt;\', 0)</span>\n' + '&lt;int&gt; = int(<span class="hljs-string">\'±0b&lt;bin&gt;\'</span>, <span class="hljs-number">0</span>) <span class="hljs-comment"># Or: int(\'±0x&lt;hex&gt;\', 0)</span>\n' +
'&lt;str&gt; = bin(&lt;int&gt;) <span class="hljs-comment"># Returns \'[-]0b&lt;bin&gt;\'. Also hex().</span>\n'; '&lt;str&gt; = bin(&lt;int&gt;) <span class="hljs-comment"># Returns \'[-]0b&lt;bin&gt;\'. Also hex().</span>\n';
const LRU_CACHE =
'<span class="hljs-keyword">from</span> functools <span class="hljs-keyword">import</span> lru_cache\n' +
const CACHE =
'<span class="hljs-keyword">from</span> functools <span class="hljs-keyword">import</span> cache\n' +
'\n' + '\n' +
'<span class="hljs-meta">@lru_cache(maxsize=None)</span>\n' +
'<span class="hljs-meta">@cache</span>\n' +
'<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">fib</span><span class="hljs-params">(n)</span>:</span>\n' + '<span class="hljs-function"><span class="hljs-keyword">def</span> <span class="hljs-title">fib</span><span class="hljs-params">(n)</span>:</span>\n' +
' <span class="hljs-keyword">return</span> n <span class="hljs-keyword">if</span> n &lt; <span class="hljs-number">2</span> <span class="hljs-keyword">else</span> fib(n-<span class="hljs-number">2</span>) + fib(n-<span class="hljs-number">1</span>)\n';
' <span class="hljs-keyword">return</span> n <span class="hljs-keyword">if</span> n &lt; <span class="hljs-number">2</span> <span class="hljs-keyword">else</span> fib(n-<span class="hljs-number">2</span>) + fib(n-<span class="hljs-number">1</span>)';
const PARAMETRIZED_DECORATOR = const PARAMETRIZED_DECORATOR =
'<span class="hljs-keyword">from</span> functools <span class="hljs-keyword">import</span> wraps\n' + '<span class="hljs-keyword">from</span> functools <span class="hljs-keyword">import</span> wraps\n' +
@ -838,7 +838,7 @@ function fixClasses() {
function fixHighlights() { function fixHighlights() {
$(`code:contains(<int> = ±0b<bin>)`).html(BIN_HEX); $(`code:contains(<int> = ±0b<bin>)`).html(BIN_HEX);
$(`code:contains(@lru_cache(maxsize=None))`).html(LRU_CACHE);
$(`code:contains(@cache)`).html(CACHE);
$(`code:contains(@debug(print_result=True))`).html(PARAMETRIZED_DECORATOR); $(`code:contains(@debug(print_result=True))`).html(PARAMETRIZED_DECORATOR);
$(`code:contains(print/str/repr([<obj>]))`).html(REPR_USE_CASES); $(`code:contains(print/str/repr([<obj>]))`).html(REPR_USE_CASES);
$(`code:contains((self, a=None):)`).html(CONSTRUCTOR_OVERLOADING); $(`code:contains((self, a=None):)`).html(CONSTRUCTOR_OVERLOADING);

4
web/faq.html
View File

@ -1,6 +1,6 @@
<details open><summary><strong>Which Python version is this for?</strong></summary><br> <details open><summary><strong>Which Python version is this for?</strong></summary><br>
&nbsp;&nbsp;&nbsp;&nbsp;Everything should work in the latest Python version, which is 3.12. Every feature that requires version higher than 3.8 has that mentioned in comments or brackets. There are only six such features, four requiring 3.9, and two requiring 3.10.<br><br>
&nbsp;&nbsp;&nbsp;&nbsp;As of 12th March 2024, the only libraries whose latest version requires Python version higher than 3.8 are: numpy, pandas and matplotlib. They all require Python 3.9. This cheatsheet covers pandas library version 2.0 or higher which was released on 3rd April 2023.
&nbsp;&nbsp;&nbsp;&nbsp;Everything should work in the latest Python version, which is 3.12. Every feature that requires version higher than 3.9 has that mentioned in comments or brackets. There are only two such features, both requiring 3.10.<br><br>
&nbsp;&nbsp;&nbsp;&nbsp;As of 12th March 2024, the only libraries whose latest version requires Python version higher than 3.8 are: numpy, pandas and matplotlib. They all require Python 3.9. This cheatsheet covers numpy version numpy 2.0 (or higher) that was released on 16th June, 2024 pandas version 2.0 (or higher) that was released on 3rd April 2023.
</details><br> </details><br>
<details open><summary><strong>How to use it?</strong></summary><br> <details open><summary><strong>How to use it?</strong></summary><br>

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