print 3 . 5;  # 35
print 3.5;    # 3.5
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Warnings will catch that for you.

%foo = (bar => "xyzzy")
print "-$foo{bar}-";   # -xyzzy-
print "-$foo {bar}-";  # - {bar}-
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Putting a space in the middle of a variable is just a wee bit different from indenting lines within a function.

$a = 1;
print $a - -5;  # 6
print $a -- 5;  # error

print q qhelloq;  # hello
print qqhelloq;   # qqhelloq
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All of these examples are highly contrived, and not at all the same as wanting to indent lines to properly reflect a nested structure and being told that no, those lines should not be indented, because the leading whitespace is significant. And as for having blank lines be significant... the English language lacks the words to describe my view of that. At this point I'm thinking I'll probably continue to use comments as I have been doing, after all. The prospect of being able to automatically generate documentation from the POD comments embedded in the code was attractive to me in principle, but apparently it's not flexible enough to be used at all the way I want.

$;=sub{$/};@;=map{my($a,$b)=($_,$;);$;=sub{$a.$b->()}}
split//,".rekcah lreP rehtona tsuJ";$\=$ ;->();print$/
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