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49 lines
738 B
C
49 lines
738 B
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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/* functions
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*/
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u3_noun
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u3_cqa_inc(u3_atom a)
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{
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return u3_ci_vint(u3k(a));
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}
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u3_noun
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u3_cqa_dec(u3_atom a)
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{
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if ( 0 == a ) {
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return u3_cm_error("decrement-underflow");
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}
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else {
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if ( u3_so(u3_ca_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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u3_cr_mp(a_mp, a);
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mpz_sub_ui(a_mp, a_mp, 1);
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return u3_ci_mp(a_mp);
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}
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}
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}
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u3_noun
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u3_cwa_dec(u3_noun cor)
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{
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u3_noun a;
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if ( (u3_none == (a = u3_cr_at(u3_cv_sam, cor))) ||
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(u3_no == u3ud(a)) )
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{
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return u3_cm_bail(c3__exit);
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} else {
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return u3_cqa_dec(a);
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}
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}
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