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57 lines
880 B
C
57 lines
880 B
C
/* j/3/tape.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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static u2_noun
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_norm(
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u2_noun a)
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{
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if ( u2_no == u2du(a) ) {
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return u2_nul;
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} else {
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return u2nc(((u2_yes == u2du(u2h(a))) ? u2_nul : u2k(u2h(a))),
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_norm(u2t(a)));
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}
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}
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static u2_bean
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_good(
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u2_noun a)
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{
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while ( 1 ) {
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if ( u2_nul == a ) {
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return u2_yes;
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}
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if ( u2_no == u2ud(u2h(a)) ) {
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return u2_no;
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}
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a = u2t(a);
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}
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}
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u2_noun
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u2_cqe_tape(u2_noun a)
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{
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if ( u2_yes == _good(a) ) {
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return u2k(a);
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} else {
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return _norm(a);
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}
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}
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u2_noun
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u2_cwe_tape(u2_noun cor)
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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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return u2_cm_bail(c3__fail);
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} else {
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return u2_cqe_tape(a);
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}
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}
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