pp.c:pp_negate: Move looks_like_number where it matters

Since we already have a check further down to see whether a string
begins with an identifier or sign, and since looks_like_number
was added for strings representing negative numbers, move the
looks_like_number down to where we already know the string
begins with '-'.

This is a micro-optimisation, but it also makes the code more
straightforward (to me at least).

This happens to let magical integers-as-strings fall down to code that
they used not to reach, so that has to change to account.

diff --git a/pp.c b/pp.c
index 811d185..0066513 100644 (file)
--- a/pp.c
+++ b/pp.c
@@ -2157,10 +2157,6 @@ PP(pp_negate)
     {
        SV * const sv = TOPs;
 
-        if( !SvNIOK( sv ) && looks_like_number( sv ) ){
-           SvIV_please_nomg( sv );
-        }   
-
        if (SvIOK(sv) || (SvGMAGICAL(sv) && SvIOKp(sv))) {
            /* It's publicly an integer */
        oops_its_an_int:
@@ -2195,16 +2191,14 @@ PP(pp_negate)
                sv_setpvs(TARG, "-");
                sv_catsv(TARG, sv);
            }
-           else if (*s == '+' || *s == '-') {
+           else if (*s == '+' || (*s == '-' && !looks_like_number(sv))) {
                sv_setsv_nomg(TARG, sv);
                *SvPV_force_nomg(TARG, len) = *s == '-' ? '+' : '-';
            }
-           else {
-               SvIV_please_nomg(sv);
-               if (SvIOK(sv))
+           else if (SvIV_please_nomg(sv))
                  goto oops_its_an_int;
+           else
                sv_setnv(TARG, -SvNV_nomg(sv));
-           }
            SETTARG;
        }
        else