This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
add comment explaining a subtlety
[perl5.git] / regcomp.c
index 916f9ba..d0133fe 100644 (file)
--- a/regcomp.c
+++ b/regcomp.c
@@ -18214,6 +18214,9 @@ S_reginsert(pTHX_ RExC_state_t *pRExC_state, U8 op, regnode *opnd, U32 depth)
     if (RExC_open_parens) {
         int paren;
         /*DEBUG_PARSE_FMT("inst"," - %"IVdf, (IV)RExC_npar);*/
+        /* remember that RExC_npar is rex->nparens + 1,
+         * iow it is 1 more than the number of parens seen in
+         * the pattern so far. */
         for ( paren=0 ; paren < RExC_npar ; paren++ ) {
             if ( RExC_open_parens[paren] >= opnd ) {
                 /*DEBUG_PARSE_FMT("open"," - %d",size);*/