@lstrojny I will _soon_ stop to argue (at the end of this comment :laughing:)

    $foo_ . $bar . "\n"

Wasn't that hard to find out :smile: What I want to say is, that I wouldn't name it "new class of hard to spot bugs". In this code is no `_` within the string, but if it would be (or in any other case of ambiguity, or even possible ambiguity) one can/should use braces

    "{$foo}_{$bar}\n"

which I for myself still find more readable/clear.

What I _really_ wanted to say: In obvious cases (like this one) I don't see any issue. In non-obvious cases I agree with you, that interpolation should be substituted with (e.g.) `sprintf()`, or similar.

(My 2 cent at the end: Concatenation is just something for string _building_, not _creation_. Of course there are exceptions).


I'll revert it later. Argueing about code-styles definitely nothing I want to waste my time for (anymore :wink:)