From: "ioquatix (Samuel Williams) via ruby-core" Date: 2023-03-15T08:40:11+00:00 Subject: [ruby-core:112892] [Ruby master Bug#19485] Unexpected behavior in squiggly heredocs Issue #19485 has been updated by ioquatix (Samuel Williams). I don't think it's a good idea to assume a tab is 8 spaces. Regarding indentation, it might be a nice simplification to only consider the first line in the squiggly heredoc. That's what I've done in the past - it's predictable and easy to explain. i.e. ``` x = <<~FOO 1 2 3 FOO ``` At most 4 spaces is removed from each line. The first line determines this. Anyway, maybe it's irrelevant to this discussion. But that's how I've implemented it in my own language/interpreter in the past. ---------------------------------------- Bug #19485: Unexpected behavior in squiggly heredocs https://bugs.ruby-lang.org/issues/19485#change-102408 * Author: jemmai (Jemma Issroff) * Status: Assigned * Priority: Normal * Assignee: core * ruby -v: 3.2.1 * Backport: 2.7: UNKNOWN, 3.0: REQUIRED, 3.1: REQUIRED, 3.2: REQUIRED ---------------------------------------- Based on [the squiggly heredoc documentation](https://ruby-doc.org/3.2.1/syntax/literals_rdoc.html), I found the following to be unexpected behavior. Explicitly, the documentation specifies, "The indentation of the least-indented line will be removed from each line of the content." After running: ```ruby File.write("test.rb", "p <<~EOF\n\ta\n b\nEOF\n") ``` and then `ruby test.rb`, I get the following output: ``` "\ta\nb\n" ``` The least-indented line above is ` b`, however, no leading whitespace is removed from the line containing `\ta`. For another example: ```ruby File.write("test.rb", "p <<~EOF\n\tA\n \tB\nEOF\n") ``` `ruby test.rb` gives: ``` "A\nB\n" ``` In this case, the `\t` was removed from the line containing `A`, but more whitespace than that (` \t`) was removed from the line containing `B`. After seeing the first example, I assumed that the documentation was out of date, and that I should fix it to read that `\t` would never be converted into space characters in order to remove leading whitespace. But after the second example, it seems like this is a bug in removing leading whitespace. Can someone please explain what the rules should be on squiggly heredocs? I can implement a fix to adhere to the rules, or can update the documentation, I am just unsure of what the rules should be because the above two examples reflect unexpected behavior in two distinct ways. -- https://bugs.ruby-lang.org/ ______________________________________________ ruby-core mailing list -- ruby-core@ml.ruby-lang.org To unsubscribe send an email to ruby-core-leave@ml.ruby-lang.org ruby-core info -- https://ml.ruby-lang.org/mailman3/postorius/lists/ruby-core.ml.ruby-lang.org/