/*
* call-seq:
* Encoding.compatible?(str1, str2) -> enc or nil
*
* Checks the compatibility of two strings.
* If they are compatible, means concatenatable,
* returns an encoding which the concatenated string will be.
* If they are not compatible, nil is returned.
*
* Encoding.compatible?("\xa1".force_encoding("iso-8859-1"), "b")
* #=> #<Encoding:ISO-8859-1>
*
* Encoding.compatible?(
* "\xa1".force_encoding("iso-8859-1"),
* "\xa1\xa1".force_encoding("euc-jp"))
* #=> nil
*
*/
static VALUE
enc_compatible_p(VALUE klass, VALUE str1, VALUE str2)
{
rb_encoding *enc;
if (!enc_capable(str1)) return Qnil;
if (!enc_capable(str2)) return Qnil;
enc = rb_enc_compatible(str1, str2);
if (!enc) return Qnil;
return rb_enc_from_encoding(enc);
}
static void
enc_set_index(VALUE obj, int idx)
{
if (!enc_capable(obj)) {
rb_raise(rb_eArgError, "cannot set encoding on non-encoding capable object");
}
if (idx < ENCODING_INLINE_MAX) {
ENCODING_SET_INLINED(obj, idx);
return;
}
ENCODING_SET_INLINED(obj, ENCODING_INLINE_MAX);
rb_ivar_set(obj, rb_id_encoding(), INT2NUM(idx));
}
int
rb_enc_capable(VALUE obj)
{
return enc_capable(obj);
}
