mirror of
https://github.com/ytdl-org/youtube-dl.git
synced 2024-11-13 10:51:12 +00:00
[README.md] Move code from #21939 to the right place
This commit is contained in:
parent
4f2d735803
commit
d9d3a5a816
66
README.md
66
README.md
|
@ -1216,6 +1216,72 @@ Incorrect:
|
|||
'PLMYEtVRpaqY00V9W81Cwmzp6N6vZqfUKD4'
|
||||
```
|
||||
|
||||
### Inline values
|
||||
|
||||
Extracting variables is acceptable for reducing code duplication and improving readability of complex expressions. However, you should avoid extracting variables used only once and moving them to opposite parts of the extractor file, which makes reading the linear flow difficult.
|
||||
|
||||
#### Example
|
||||
|
||||
Correct:
|
||||
|
||||
```python
|
||||
title = self._html_search_regex(r'<title>([^<]+)</title>', webpage, 'title')
|
||||
```
|
||||
|
||||
Incorrect:
|
||||
|
||||
```python
|
||||
TITLE_RE = r'<title>([^<]+)</title>'
|
||||
# ...some lines of code...
|
||||
title = self._html_search_regex(TITLE_RE, webpage, 'title')
|
||||
```
|
||||
|
||||
### Collapse fallbacks
|
||||
|
||||
Multiple fallback values can quickly become unwieldy. Collapse multiple fallback values into a single expression via a list of patterns.
|
||||
|
||||
#### Example
|
||||
|
||||
Good:
|
||||
|
||||
```python
|
||||
description = self._html_search_meta(
|
||||
['og:description', 'description', 'twitter:description'],
|
||||
webpage, 'description', default=None)
|
||||
```
|
||||
|
||||
Unwieldy:
|
||||
|
||||
```python
|
||||
description = (
|
||||
self._og_search_description(webpage, default=None)
|
||||
or self._html_search_meta('description', webpage, default=None)
|
||||
or self._html_search_meta('twitter:description', webpage, default=None))
|
||||
```
|
||||
|
||||
Methods supporting list of patterns are: `_search_regex`, `_html_search_regex`, `_og_search_property`, `_html_search_meta`.
|
||||
|
||||
### Trailing parentheses
|
||||
|
||||
Always move trailing parentheses after the last argument.
|
||||
|
||||
#### Example
|
||||
|
||||
Correct:
|
||||
|
||||
```python
|
||||
lambda x: x['ResultSet']['Result'][0]['VideoUrlSet']['VideoUrl'],
|
||||
list)
|
||||
```
|
||||
|
||||
Incorrect:
|
||||
|
||||
```python
|
||||
lambda x: x['ResultSet']['Result'][0]['VideoUrlSet']['VideoUrl'],
|
||||
list,
|
||||
)
|
||||
```
|
||||
|
||||
### Use convenience conversion and parsing functions
|
||||
|
||||
Wrap all extracted numeric data into safe functions from [`youtube_dl/utils.py`](https://github.com/ytdl-org/youtube-dl/blob/master/youtube_dl/utils.py): `int_or_none`, `float_or_none`. Use them for string to number conversions as well.
|
||||
|
|
Loading…
Reference in New Issue
Block a user