Re: One-line heredoc for better syntax highlightning

On 19/09/2022 20:10, Olle Härstedt wrote:

More for users to learn? Don't you mean less, haha? This is an arbitrary limitation of heredoc, that we can remove (it might not be arbitrary from a yacc perspective, someone would have to explain that if so).

I don't think the rules for heredoc are arbitrary,  but they are quite specific: the end delimiter has to appear at the *start* of a line, so it can appear anywhere else in the text without prematurely ending the string: $foo = <<<FOO This is a normal heredoc this is not the end FOO this is: FOO; (Prior to PHP 7.3, only certain characters could appear *after* the end delimiter, but that's now more relaxed, and there's some clever rules around indenting.) As far as I can see, a single-line heredoc would need to be a new syntax, with its own syntax rules. Something like * If there is at least one non-whitespace character after <<<FOO but before the next newline, this is a one-line heredoc * If so, the heredoc content is everything up to and including the last occurrence of "FOO", followed by an optional semicolon, and a required newline * If "FOO" does not appear again before the next newline; or there is other text between "FOO" and the newline, that is a syntax error For instance, the following would presumably be valid: $foo = <<<FOO one-line heredoc ending at end of line FOO ; $foo = <<<FOO one-line heredoc with semicolon FOO; $foo = <<<FOO this is a heredoc containing FOO and other text FOO; $foo = <<<FOO // I guess this is a string not a comment? FOO; But the following would not: $foo = <<<FOO one-line heredoc not ended $foo = <<<FOO this heredoc contains FOO and then doesn't end $foo = <<<FOO mixing one-line and multi-line syntax doesn't make sense FOO; $foo = <<<FOO this heredoc looks like it ends FOO . 'but actually it doesn't'; Perhaps you disagree with some of those rules and examples, but hopefully can see that the rules would need defining, and therefore learning.

I don't know about other editors, but PhpStorm at least also recognises an in-line comment explicitly labelling any string, which if anything seems m ore explicit: $query = /** @lang mysql */"SELECT * FROM foo";

Pja. I wouldn't call it more or less explicit than heredoc notation, personally.

It's more explicit in the sense that it is syntax dedicated for that purpose, in a standard format. If I write <<<FOO hello FOO, there's no way to know if "foo" is the name of a language I'm hoping to label, or just a token which I know doesn't appear in my content; if I write /** @lang foo */"hello", there's no ambiguity, even if you've never heard of "foo" as a language. Regards, -- Rowan Tommins [IMSoP]