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href="../tools/pacman.html"><strong aria-hidden="true">1.12.</strong> pacman</a></li></ol></li><li class="expanded "><a href="../monitor/index.html"><strong aria-hidden="true">2.</strong> Resource analysis & monitor</a></li><li><ol class="section"><li class="expanded "><a href="../monitor/lsof.html"><strong aria-hidden="true">2.1.</strong> lsof</a></li><li class="expanded "><a href="../monitor/ss.html"><strong aria-hidden="true">2.2.</strong> ss</a></li><li class="expanded "><a href="../monitor/pidstat.html"><strong aria-hidden="true">2.3.</strong> pidstat</a></li><li class="expanded "><a href="../monitor/pgrep.html"><strong aria-hidden="true">2.4.</strong> pgrep</a></li><li class="expanded "><a href="../monitor/pmap.html"><strong aria-hidden="true">2.5.</strong> pmap</a></li><li class="expanded "><a href="../monitor/pstack.html"><strong aria-hidden="true">2.6.</strong> pstack</a></li></ol></li><li class="expanded "><a href="../trace_profile/index.html"><strong aria-hidden="true">3.</strong> Trace and Profile</a></li><li><ol class="section"><li class="expanded "><a href="../trace_profile/strace.html"><strong aria-hidden="true">3.1.</strong> strace</a></li><li class="expanded "><a href="../trace_profile/ltrace.html"><strong aria-hidden="true">3.2.</strong> ltrace</a></li><li class="expanded "><a href="../trace_profile/perf.html"><strong aria-hidden="true">3.3.</strong> perf</a></li><li class="expanded "><a href="../trace_profile/oprofile.html"><strong aria-hidden="true">3.4.</strong> OProfile</a></li><li class="expanded "><a href="../trace_profile/time.html"><strong aria-hidden="true">3.5.</strong> time</a></li></ol></li><li class="expanded "><a href="../binary/index.html"><strong aria-hidden="true">4.</strong> Binary</a></li><li><ol class="section"><li class="expanded "><a href="../binary/od.html"><strong aria-hidden="true">4.1.</strong> od</a></li><li class="expanded "><a href="../binary/xxd.html"><strong aria-hidden="true">4.2.</strong> xxd</a></li><li class="expanded "><a href="../binary/readelf.html"><strong aria-hidden="true">4.3.</strong> readelf</a></li><li class="expanded "><a href="../binary/objdump.html"><strong aria-hidden="true">4.4.</strong> objdump</a></li><li class="expanded "><a href="../binary/nm.html"><strong aria-hidden="true">4.5.</strong> nm</a></li></ol></li><li class="expanded "><a href="../development/index.html"><strong aria-hidden="true">5.</strong> Development</a></li><li><ol class="section"><li class="expanded "><a href="../development/c++filt.html"><strong aria-hidden="true">5.1.</strong> c++filt</a></li><li class="expanded "><a href="../development/c++.html"><strong aria-hidden="true">5.2.</strong> c++</a></li><li class="expanded "><a href="../development/glibc.html"><strong aria-hidden="true">5.3.</strong> glibc</a></li><li class="expanded "><a href="../development/gcc.html"><strong aria-hidden="true">5.4.</strong> gcc</a></li><li class="expanded "><a href="../development/make.html"><strong aria-hidden="true">5.5.</strong> make</a></li><li class="expanded "><a href="../development/ld.so.html"><strong aria-hidden="true">5.6.</strong> ld.so</a></li><li class="expanded "><a href="../development/symbolver.html"><strong aria-hidden="true">5.7.</strong> symbol versioning</a></li><li class="expanded "><a href="../development/python.html" class="active"><strong aria-hidden="true">5.8.</strong> python</a></li></ol></li><li class="expanded "><a href="../arch/index.html"><strong aria-hidden="true">6.</strong> Arch</a></li><li><ol class="section"><li class="expanded "><a href="../arch/x86_64.html"><strong aria-hidden="true">6.1.</strong> x86_64</a></li><li class="expanded "><a href="../arch/arm64.html"><strong aria-hidden="true">6.2.</strong> arm64</a></li><li class="expanded "><a href="../arch/armv7.html"><strong aria-hidden="true">6.3.</strong> armv7</a></li></ol></li></ol> + </div> + <div id="sidebar-resize-handle" 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(Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar"> + <i class="fa fa-search"></i> + </button> + + </div> + + <h1 class="menu-title">Notes</h1> + + <div class="right-buttons"> + <a href="../print.html" title="Print this book" aria-label="Print this book"> + <i id="print-button" class="fa fa-print"></i> + </a> + + <a href="https://github.com/johannst/notes" title="Git repository" aria-label="Git repository"> + <i id="git-repository-button" class="fa fa-github"></i> + </a> + + </div> + </div> + </div> + + + <div id="search-wrapper" class="hidden"> + <form id="searchbar-outer" class="searchbar-outer"> + <input type="search" name="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header"> + </form> + <div id="searchresults-outer" class="searchresults-outer hidden"> + <div id="searchresults-header" class="searchresults-header"></div> + <ul id="searchresults"> + </ul> + </div> + </div> + + + <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM --> + <script type="text/javascript"> + document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible'); + document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible'); + Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) { + link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1); + }); + </script> + + <div id="content" class="content"> + <main> + <h1><a class="header" href="#python" id="python">python</a></h1> +<h2><a class="header" href="#decorator-a-hrefhttpswwwonline-pythoncomiddie0gpyuruna" id="decorator-a-hrefhttpswwwonline-pythoncomiddie0gpyuruna">Decorator [<a href="https://www.online-python.com/IDdiE0gpYU">run</a>]</a></h2> +<p>Some decorator examples with type annotation.</p> +<pre><code class="language-python">from typing import Callable + +def log(f: Callable[[int], None]) -> Callable[[int], None]: + def inner(x: int): + print(f"log::inner f={f.__name__} x={x}") + f(x) + return inner + +@log +def some_fn(x: int): + print(f"some_fn x={x}") + + +def log_tag(tag: str) -> Callable[[Callable[[int], None]], Callable[[int], None]]: + def decorator(f: Callable[[int], None]) -> Callable[[int], None]: + def inner(x: int): + print(f"log_tag::inner f={f.__name__} tag={tag} x={x}") + f(x) + return inner + return decorator + +@log_tag("some_tag") +def some_fn2(x: int): + print(f"some_fn2 x={x}") +</code></pre> +<h2><a class="header" href="#walrus-operator-a-hrefhttpswwwonline-pythoncom9t12pvmkvyruna" id="walrus-operator-a-hrefhttpswwwonline-pythoncom9t12pvmkvyruna">Walrus operator [<a href="https://www.online-python.com/9T12PvmKVy">run</a>]</a></h2> +<p>Walrus operator <code>:=</code> added since <strong>python 3.8</strong>.</p> +<pre><code class="language-python">from typing import Optional + +# Example 1: if let statements + +def foo(ret: Optional[int]) -> Optional[int]: + return ret + +if r := foo(None): + print(f"foo(None) -> {r}") + +if r := foo(1337): + print(f"foo(1337) -> {r}") + +# Example 2: while let statements + +toks = iter(['a', 'b', 'c']) +while tok := next(toks, None): + print(f"{tok}") + +# Example 3: list comprehension + +print([tok for t in [" a", " ", " b "] if (tok := t.strip())]) +</code></pre> +<h2><a class="header" href="#a-hrefhttpsdocspythonorg3libraryunittesthtmlunittesta-a-hrefhttpswwwonline-pythoncom2fit4ucbziruna" id="a-hrefhttpsdocspythonorg3libraryunittesthtmlunittesta-a-hrefhttpswwwonline-pythoncom2fit4ucbziruna"><a href="https://docs.python.org/3/library/unittest.html">Unittest</a> [<a href="https://www.online-python.com/2fit4UcbzI">run</a>]</a></h2> +<p>Run unittests directly from the command line as <br /> +<code>python3 -m unittest -v test</code></p> +<p>Optionally pass <code>-k <patter></code> to only run subset of tests.</p> +<pre><code class="language-python"># file: test.py + +import unittest + +class MyTest(unittest.TestCase): + def setUp(self): + pass + def tearDown(self): + pass + # Tests need to start with the prefix 'test'. + def test_foo(self): + self.assertEqual(1 + 2, 3) + def test_bar(self): + with self.assertRaises(IndexError): + list()[0] +</code></pre> +<h2><a class="header" href="#a-hrefhttpsdocspythonorg3librarydoctesthtmldoctesta-a-hrefhttpswwwonline-pythoncomlzst51unihruna" id="a-hrefhttpsdocspythonorg3librarydoctesthtmldoctesta-a-hrefhttpswwwonline-pythoncomlzst51unihruna"><a href="https://docs.python.org/3/library/doctest.html">Doctest</a> [<a href="https://www.online-python.com/LZst51UNIH">run</a>]</a></h2> +<p>Run doctests directly from the command line as <br /> +<code>python -m doctest -v test.py</code></p> +<pre><code class="language-python"># file: test.py + +def sum(a: int, b: int) -> int: + """Sum a and b. + + >>> sum(1, 2) + 3 + + >>> sum(10, 20) + 30 + """ + return a + b +</code></pre> +<h2><a class="header" href="#a-hrefhttpsdocspythonorg3librarytimeithtmltimeita" id="a-hrefhttpsdocspythonorg3librarytimeithtmltimeita"><a href="https://docs.python.org/3/library/timeit.html">timeit</a></a></h2> +<p>Micro benchmarking.</p> +<pre><code class="language-bash">python -m timeit '[x.strip() for x in ["a ", " b"]]' +</code></pre> + + </main> + + <nav class="nav-wrapper" aria-label="Page navigation"> + <!-- Mobile navigation buttons --> + + <a rel="prev" href="../development/symbolver.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left"> + <i class="fa fa-angle-left"></i> + </a> + + + + <a rel="next" href="../arch/index.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right"> + <i class="fa fa-angle-right"></i> + </a> + + + <div style="clear: both"></div> + </nav> + </div> + </div> + + <nav class="nav-wide-wrapper" aria-label="Page navigation"> + + <a href="../development/symbolver.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left"> + <i class="fa fa-angle-left"></i> + </a> + + + + <a href="../arch/index.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right"> + <i class="fa fa-angle-right"></i> + </a> + + </nav> + + </div> + + + + + + + + + <script type="text/javascript"> + window.playpen_copyable = true; + </script> + + + + + + <script src="../elasticlunr.min.js" type="text/javascript" charset="utf-8"></script> + <script src="../mark.min.js" type="text/javascript" charset="utf-8"></script> + <script src="../searcher.js" type="text/javascript" charset="utf-8"></script> + + + <script src="../clipboard.min.js" type="text/javascript" charset="utf-8"></script> + <script src="../highlight.js" type="text/javascript" charset="utf-8"></script> + <script src="../book.js" type="text/javascript" charset="utf-8"></script> + + <!-- Custom JS scripts --> + + + + + </body> +</html> |