Issue #12694 has been updated by znz (Kazuhiro NISHIYAMA). > `str.sub(/^#{Regexp.escape(substr)}/, '') #=> 'def'` I think `^` should be `\A` in description of this ticket. (and maybe in handle_tag_name_mixin.rb of fluentd too) Which is expected?: first prefix of string only or prefix of each line ---------------------------------------- Feature #12694: Want a String method to remove heading substr https://bugs.ruby-lang.org/issues/12694#change-65195 * Author: sonots (Naotoshi Seo) * Status: Open * Priority: Normal * Assignee: * Target version: ---------------------------------------- I often write codes like: ```ruby str = 'abcdef' substr = 'abc' str[substr.size..-1] if str.start_with?(substr) #=> 'def' # or str.sub(/^#{Regexp.escape(substr)}/, '') #=> 'def' ``` I want a short hand which is something like: ```ruby str = 'abcdef' substr = 'abc' str.lstrip(substr) #=> 'def' ``` Having similar argument for `String#rstrip` would be nice for symmetry although we already have `String#chomp(substr)` My frequent use-case is coming from fluentd. We have `remove_tag_prefix` option to remove a heading substring from a tag. We currently using `String#sub` with a regular expression, but I feel regular expression matching is too much just to remove a heading substring. https://github.com/fluent/fluentd/blob/75005f18d48ed3d416890413fa5f83982b264c71/lib/fluent/compat/handle_tag_name_mixin.rb#L45 -- https://bugs.ruby-lang.org/ Unsubscribe: <mailto:ruby-core-request / ruby-lang.org?subject=unsubscribe> <http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>