From 6702c788683c7ac40a3ccbf1e4af3bca3734e75a Mon Sep 17 00:00:00 2001 From: Vadim Nifadev <36514612+nifadyev@users.noreply.github.com> Date: Tue, 15 Oct 2024 17:42:15 +0300 Subject: [PATCH] Fix images source in notebook --- irrelevant/wtf.ipynb | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/irrelevant/wtf.ipynb b/irrelevant/wtf.ipynb index c037032..809c17f 100644 --- a/irrelevant/wtf.ipynb +++ b/irrelevant/wtf.ipynb @@ -355,7 +355,7 @@ " * All length 0 and length 1 strings are interned.\n", " * Strings are interned at compile time (`'wtf'` will be interned but `''.join(['w', 't', 'f'])` will not be interned)\n", " * Strings that are not composed of ASCII letters, digits or underscores, are not interned. This explains why `'wtf!'` was not interned due to `!`. CPython implementation of this rule can be found [here](https://github.com/python/cpython/blob/3.6/Objects/codeobject.c#L19)\n", - " ![String interning process](https://raw.githubusercontent.com/nifadyev/wtfpython/refs/heads/feature/%2374/add-dark-theme-and-alt-support-for-images/images/string-intern/string_interning.svg)\n", + "\"Shows\n", "+ When `a` and `b` are set to `\"wtf!\"` in the same line, the Python interpreter creates a new object, then references the second variable at the same time. If you do it on separate lines, it doesn't \"know\" that there's already `\"wtf!\"` as an object (because `\"wtf!\"` is not implicitly interned as per the facts mentioned above). It's a compile-time optimization. This optimization doesn't apply to 3.7.x versions of CPython (check this [issue](https://github.com/satwikkansal/wtfpython/issues/100) for more discussion).\n", "+ A compile unit in an interactive environment like IPython consists of a single statement, whereas it consists of the entire module in case of modules. `a, b = \"wtf!\", \"wtf!\"` is single statement, whereas `a = \"wtf!\"; b = \"wtf!\"` are two statements in a single line. This explains why the identities are different in `a = \"wtf!\"; b = \"wtf!\"`, and also explain why they are same when invoked in `some_file.py`\n", "+ The abrupt change in the output of the fourth snippet is due to a [peephole optimization](https://en.wikipedia.org/wiki/Peephole_optimization) technique known as Constant folding. This means the expression `'a'*20` is replaced by `'aaaaaaaaaaaaaaaaaaaa'` during compilation to save a few clock cycles during runtime. Constant folding only occurs for strings having a length of less than 21. (Why? Imagine the size of `.pyc` file generated as a result of the expression `'a'*10**10`). [Here's](https://github.com/python/cpython/blob/3.6/Python/peephole.c#L288) the implementation source for the same.\n", @@ -2947,11 +2947,11 @@ "\n", "When we initialize `row` variable, this visualization explains what happens in the memory\n", "\n", - "\"Shows\n", + "\"Shows\n", "\n", "And when the `board` is initialized by multiplying the `row`, this is what happens inside the memory (each of the elements `board[0]`, `board[1]` and `board[2]` is a reference to the same list referred by `row`)\n", "\n", - "\"Shows\n", + "\"Shows\n", "\n", "We can avoid this scenario here by not using `row` variable to generate `board`. (Asked in [this](https://github.com/satwikkansal/wtfpython/issues/68) issue).\n", "\n"