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instance method
StringScanner#[]
[](n)
ext/strscan/strscan.c
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static VALUE
strscan_aref(VALUE self, VALUE idx)
{
const char *name;
struct strscanner *p;
long i;
GET_SCANNER(self, p);
if (! MATCHED_P(p)) return Qnil;
switch (TYPE(idx)) {
case T_SYMBOL:
idx = rb_sym2str(idx);
/* fall through */
case T_STRING:
if (!RTEST(p->regex)) return Qnil;
RSTRING_GETMEM(idx, name, i);
i = name_to_backref_number(&(p->regs), p->regex, name, name + i, rb_enc_get(idx));
break;
default:
i = NUM2LONG(idx);
}
if (i < 0)
i += p->regs.num_regs;
if (i < 0) return Qnil;
if (i >= p->regs.num_regs) return Qnil;
if (p->regs.beg[i] == -1) return Qnil;
return extract_range(p,
adjust_register_position(p, p->regs.beg[i]),
adjust_register_position(p, p->regs.end[i]));
}
Returns the n-th subgroup in the most recent match.
Example
s = StringScanner.new("Fri Dec 12 1975 14:39") s.scan(/(\w+) (\w+) (\d+) /) # -> "Fri Dec 12 " s[0] # -> "Fri Dec 12 " s[1] # -> "Fri" s[2] # -> "Dec" s[3] # -> "12" s.post_match # -> "1975 14:39" s.pre_match # -> "" s.reset s.scan(/(?<wday>\w+) (?<month>\w+) (?<day>\d+) /) # -> "Fri Dec 12 " s[0] # -> "Fri Dec 12 " s[1] # -> "Fri" s[2] # -> "Dec" s[3] # -> "12" s[:wday] # -> "Fri" s[:month] # -> "Dec" s[:day] # -> "12" s.post_match # -> "1975 14:39" s.pre_match # -> ""