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57 lines
1.2 KiB
C
57 lines
1.2 KiB
C
/* j/1/dec.c
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**
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** This file is in the public domain.
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*/
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#include "all.h"
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#include "../pit.h"
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/* functions
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*/
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u2_weak // transfer
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j2_mbc(Pt1, inc)(u2_atom a) // retain
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{
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return u2_ci_vint(u2k(a));
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}
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u2_weak // transfer
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j2_mbc(Pt1, dec)(u2_atom a) // retain
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{
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if ( 0 == a ) {
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return u2_cm_error("decrement-underflow");
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}
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else {
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if ( u2_so(u2_co_is_cat(a)) ) {
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return a - 1;
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}
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else {
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mpz_t a_mp;
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u2_cr_mp(a_mp, a);
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mpz_sub_ui(a_mp, a_mp, 1);
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return u2_ci_mp(a_mp);
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}
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}
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}
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u2_weak // transfer
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j2_mb(Pt1, dec)(u2_noun cor) // retain
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{
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u2_noun a;
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if ( (u2_none == (a = u2_cr_at(u2_cv_sam, cor))) ||
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(u2_no == u2ud(a)) )
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{
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return u2_cm_bail(c3__exit);
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} else {
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return j2_mbc(Pt1, dec)(a);
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}
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}
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/* structures
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*/
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u2_ho_jet
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j2_mbj(Pt1, dec)[] = {
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{ ".2", c3__lite, j2_mb(Pt1, dec), u2_jet_live, u2_none, u2_none },
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{ }
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};
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