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in reply to Re^3: Hash Syntax Question
in thread Hash Syntax Question

Well, deparse isn't 100% reliable, and secondly, it still takes some analyzing to determine that there are no strings to be interpolated in the double-quoted string.

Probably not much more than analyzing a single-quoted string for \' escapes though, since you'd only have to test for the sigils.

update: what I mean to say is, all this stuff is done at compile-time - i.e. normally, it's done only once per string; when the code is loaded. It has no impact at all after that. Run-time perl has no distinction between single and double quoted strings - it all compiles to a fixed string (for constant strings) or a number of concatenation operations on variables and constant strings (for interpolations).