static VALUE
string_to_r(VALUE self)
{
VALUE s = f_gsub(self, underscores_pat, an_underscore);
VALUE a = string_to_r_internal(s);
if (!NIL_P(RARRAY_AT(a, 0)))
return RARRAY_AT(a, 0);
return rb_rational_new1(INT2FIX(0));
}
/*
* call-seq:
* str.to_r -> rational
*
* Returns a rational which denotes the string form. The parser
* ignores leading whitespaces and trailing garbage. Any digit
* sequences can be separeted by an underscore. Returns zero for null
* or garbage string.
*
* NOTE: '0.3'.to_r isn't the same as 0.3.to_r. The former is
* equivalent to '3/10'.to_r, but the latter isn't so.
*
* For example:
*
* ' 2 '.to_r #=> (2/1)
* '300/2'.to_r #=> (150/1)
* '-9.2'.to_r #=> (-46/5)
* '-9.2e2'.to_r #=> (-920/1)
* '1_234_567'.to_r #=> (1234567/1)
* '21 june 09'.to_r #=> (21/1)
* '21/06/09'.to_r #=> (7/2)
* 'bwv 1079'.to_r #=> (0/1)
*/
static VALUE
string_to_r(VALUE self, SEL sel)
{
VALUE s, a, backref;
backref = rb_backref_get();
rb_match_busy(backref);
s = f_gsub(self, underscores_pat, an_underscore);
a = string_to_r_internal(s);
rb_backref_set(backref);
if (!NIL_P(RARRAY_PTR(a)[0]))
return RARRAY_PTR(a)[0];
return rb_rational_new1(INT2FIX(0));
}
static VALUE
string_to_r_internal(VALUE self)
{
VALUE s, m;
s = self;
if (RSTRING_LEN(s) == 0)
return rb_assoc_new(Qnil, self);
m = f_match(rat_pat, s);
if (!NIL_P(m)) {
VALUE v, ifp, exp, ip, fp;
VALUE si = f_aref(m, INT2FIX(1));
VALUE nu = f_aref(m, INT2FIX(2));
VALUE de = f_aref(m, INT2FIX(3));
VALUE re = f_post_match(m);
{
VALUE a;
a = f_split(nu, an_e_pat);
ifp = RARRAY_PTR(a)[0];
if (RARRAY_LEN(a) != 2)
exp = Qnil;
else
exp = RARRAY_PTR(a)[1];
a = f_split(ifp, a_dot_pat);
ip = RARRAY_PTR(a)[0];
if (RARRAY_LEN(a) != 2)
fp = Qnil;
else
fp = RARRAY_PTR(a)[1];
}
v = rb_rational_new1(f_to_i(ip));
if (!NIL_P(fp)) {
char *p = StringValuePtr(fp);
long count = 0;
VALUE l;
while (*p) {
if (rb_isdigit(*p))
count++;
p++;
}
l = f_expt(INT2FIX(10), LONG2NUM(count));
v = f_mul(v, l);
v = f_add(v, f_to_i(fp));
v = f_div(v, l);
}
if (!NIL_P(si) && *StringValuePtr(si) == '-')
v = f_negate(v);
if (!NIL_P(exp))
v = f_mul(v, f_expt(INT2FIX(10), f_to_i(exp)));
#if 0
if (!NIL_P(de) && (!NIL_P(fp) || !NIL_P(exp)))
return rb_assoc_new(v, rb_usascii_str_new2("dummy"));
#endif
if (!NIL_P(de))
v = f_div(v, f_to_i(de));
return rb_assoc_new(v, re);
}
return rb_assoc_new(Qnil, self);
}
/*
* call-seq:
* int.to_r -> rational
*
* Returns the value as a rational.
*
* For example:
*
* 1.to_r #=> (1/1)
* (1<<64).to_r #=> (18446744073709551616/1)
*/
static VALUE
integer_to_r(VALUE self, SEL sel)
{
return rb_rational_new1(self);
}
/*
* call-seq:
* nil.to_r -> (0/1)
*
* Returns zero as a rational.
*/
static VALUE
nilclass_to_r(VALUE self, SEL sel)
{
return rb_rational_new1(INT2FIX(0));
}
