urbit/j/f/ut_tock.c
2014-11-17 13:56:51 -08:00

100 lines
2.2 KiB
C

/* j/6/tock.c
**
** This file is in the public domain.
*/
#include "all.h"
/* internals
*/
static u3_noun
_tock_in(
u3_noun van,
u3_noun sut,
u3_noun peh,
u3_noun mur,
u3_noun men)
{
if ( c3n == u3du(men) ) {
return u3nc(u3_nul, u3_nul);
}
else {
u3_noun i_men = u3h(men);
u3_noun pi_men = u3h(i_men);
u3_noun qi_men = u3t(i_men);
u3_noun t_men = u3t(men);
u3_noun geq = u3qfu_tack(van, pi_men, peh, mur);
u3_noun p_geq = u3h(geq);
u3_noun q_geq = u3t(geq);
u3_noun mox = _tock_in(van, sut, peh, mur, t_men);
u3_noun p_mox = u3h(mox);
u3_noun q_mox = u3t(mox);
u3_noun ret;
ret = u3nc(
( (u3_nul == p_mox)
? u3nc(u3_nul, u3k(p_geq))
: (c3n == u3r_sing(p_geq, u3t(p_mox)))
? u3m_bail(c3__exit)
: u3k(p_mox) ),
u3nc(u3nc(u3k(q_geq), u3k(qi_men)), u3k(q_mox)));
u3z(mox);
u3z(geq);
return ret;
}
}
/* functions
*/
u3_noun
_cqfu_tock(u3_noun van,
u3_noun sut,
u3_noun peh,
u3_noun mur,
u3_noun men)
{
u3_noun wib = _tock_in(van, sut, peh, mur, men);
u3_noun p_wib = u3h(wib);
u3_noun q_wib = u3t(wib);
if ( u3_nul == p_wib ) {
return u3m_bail(c3__exit);
} else {
u3_noun ret = u3nc(u3k(u3t(p_wib)), u3k(q_wib));
u3z(wib);
return ret;
}
}
/* boilerplate
*/
u3_noun
u3wfu_tock(u3_noun cor)
{
u3_noun van, sut, peh, mur, men;
if ( (c3n == u3r_mean(cor, u3x_sam_2, &peh,
u3x_sam_6, &mur,
u3x_sam_7, &men,
u3x_con, &van,
0)) ||
(u3_none == (sut = u3r_at(u3x_sam, van))) )
{
return u3m_bail(c3__fail);
} else {
return _cqfu_tock(van, sut, peh, mur, men);
}
}
u3_noun
u3qfu_tock(u3_noun van,
u3_noun sut,
u3_noun peh,
u3_noun mur,
u3_noun men)
{
return _cqfu_tock(van, sut, peh, mur, men);
}