X-Git-Url: https://git.rapsys.eu/youtubedl/blobdiff_plain/929d540d5979815dd13aa119b6fdb41454907d0c..8c72ec3993d7183e9c1fcd2cab445a3196ad8723:/README.txt?ds=sidebyside diff --git a/README.txt b/README.txt index 44cd534..045e0b1 100644 --- a/README.txt +++ b/README.txt @@ -1648,6 +1648,65 @@ Incorrect: 'https://www.youtube.com/watch?v=FqZTN594JQw&list=' '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: + + title = self._html_search_regex(r'([^<]+)', webpage, 'title') + +Incorrect: + + TITLE_RE = r'([^<]+)' + # ...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: + + description = self._html_search_meta( + ['og:description', 'description', 'twitter:description'], + webpage, 'description', default=None) + +Unwieldy: + + 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: + + lambda x: x['ResultSet']['Result'][0]['VideoUrlSet']['VideoUrl'], + list) + +Incorrect: + + lambda x: x['ResultSet']['Result'][0]['VideoUrlSet']['VideoUrl'], + list, + ) + Use convenience conversion and parsing functions Wrap all extracted numeric data into safe functions from