Re^4: Converting to number doesn't always work... (updated)

[syphilis]

I am confused why you're taking this step?

Nothing insidious or profound.
I read "this gives you the exact internal function that Perl uses to check strings and generate that warning in the first place" as implying both that:

1) if looks_like_number($x) returns true, then there will be no warning given when $x is used in numeric context;
&&
2) if looks_like_number($x) returns false, then a "non-numeric" warning will be given when $x is used in numeric context.

I find it interesting that the latter of the two is not necessarily true - furthermore, I found it so interesting that I decided to provide an example where looks_like_number($x) returns false, yet no warning is issued when $x is used in numeric context.

Your second update references the use of looks_like_number() in sv.c.
Note that Scalar::Util::looks_like_number() is a different function. (That is, it doesn't simply wrap the perl API function of the same name ... it does some other stuff as well.)

Cheers,
Rob