shrub/j/2/snag.c
2014-09-05 13:13:24 -07:00

46 lines
801 B
C

/* j/2/snag.c
**
** This file is in the public domain.
*/
#include "all.h"
/* functions
*/
u3_noun
u3_cqb_snag(u3_atom a,
u3_noun b)
{
if ( u3_ne(u3_co_is_cat(a)) ) {
return u3_cm_bail(c3__fail);
}
else {
c3_w len_w = a;
while ( len_w ) {
if ( u3_no == u3du(b) ) {
return u3_cm_bail(c3__exit);
}
b = u3t(b);
len_w--;
}
if ( u3_no == u3du(b) ) {
return u3_cm_bail(c3__exit);
}
return u3k(u3h(b));
}
}
u3_noun
u3_cwb_snag(u3_noun cor)
{
u3_noun a, b;
if ( (u3_no == u3_cr_mean(cor, u3_cv_sam_2, &a, u3_cv_sam_3, &b, 0)) ||
(u3_no == u3ud(a)) )
{
return u3_cm_bail(c3__exit);
} else {
return u3_cqb_snag(a, b);
}
}