| 1 | //
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| 2 | // Cforall Version 1.0.0 Copyright (C) 2020 University of Waterloo
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| 3 | //
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| 4 | // The contents of this file are covered under the licence agreement in the
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| 5 | // file "LICENCE" distributed with Cforall.
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| 6 | //
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| 7 | // list -- lets a user-defined stuct form intrusive linked lists
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| 8 | //
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| 9 | // Author           : Michael Brooks
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| 10 | // Created On       : Wed Apr 22 18:00:00 2020
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| 11 | // Last Modified By : Michael Brooks
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| 12 | // Last Modified On : Wed Apr 22 18:00:00 2020
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| 13 | // Update Count     : 1
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| 14 | //
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| 15 | 
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| 16 | #pragma once
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| 17 | 
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| 18 | #include <assert.h>
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| 19 | 
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| 20 | #define __DLISTED_MGD_COMMON(ELEM, NODE, LINKS_FLD) \
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| 21 | static inline ELEM& $tempcv_n2e(NODE &node) { \
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| 22 |         return node; \
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| 23 | } \
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| 24 | \
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| 25 | static inline NODE& $tempcv_e2n(ELEM &node) { \
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| 26 |         return ( NODE & ) node; \
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| 27 | } \
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| 28 | \
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| 29 | static inline ELEM & ?`prev(NODE &node) { \
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| 30 |     $dlinks(ELEM) & ls = node.LINKS_FLD; \
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| 31 |         $mgd_link(ELEM) * l = &ls.prev; \
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| 32 |         ELEM * e = l->elem; \
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| 33 |         return *e; \
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| 34 | } \
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| 35 | \
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| 36 | static inline ELEM & ?`next(NODE &node) { \
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| 37 |     $dlinks(ELEM) & ls = node.LINKS_FLD; \
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| 38 |         $mgd_link(ELEM) * l = &ls.next; \
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| 39 |         ELEM * e = l->elem; \
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| 40 |         return *e; \
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| 41 | } \
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| 42 | \
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| 43 | static inline $mgd_link(ELEM) & $prev_link(NODE &node) { \
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| 44 |     $dlinks(ELEM) & ls = node.LINKS_FLD; \
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| 45 |         $mgd_link(ELEM) * l = &ls.prev; \
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| 46 |         return *l; \
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| 47 | } \
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| 48 | \
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| 49 | static inline $mgd_link(ELEM) & $next_link(NODE &node) { \
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| 50 |     $dlinks(ELEM) & ls = node.LINKS_FLD; \
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| 51 |         $mgd_link(ELEM) * l = &ls.next; \
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| 52 |         return *l; \
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| 53 | }
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| 54 | 
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| 55 | #define __DLISTED_MGD_JUSTEXPL(STRUCT, IN_THELIST, STRUCT_IN_THELIST) \
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| 56 | struct STRUCT_IN_THELIST { \
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| 57 |         inline STRUCT; \
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| 58 | }; \
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| 59 | \
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| 60 | void ?{}(STRUCT_IN_THELIST &) = void; \
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| 61 | \
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| 62 | static inline STRUCT_IN_THELIST& ?`IN_THELIST(STRUCT &this) { \
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| 63 |         return (STRUCT_IN_THELIST&)this; \
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| 64 | }
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| 65 | 
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| 66 | #define __DLISTED_MGD_JUSTIMPL(STRUCT)
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| 67 | 
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| 68 | forall( tE & ) {
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| 69 |         struct $mgd_link {
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| 70 |                 tE *elem;
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| 71 |                 void *terminator;
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| 72 |                 _Bool is_terminator;
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| 73 |                 // will collapse to single pointer with tag bit
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| 74 |         };
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| 75 |         static inline void ?{}( $mgd_link(tE) &this, tE* elem ) {
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| 76 |                 (this.elem){ elem };
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| 77 |                 (this.terminator){ 0p };
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| 78 |                 (this.is_terminator){ 0 };
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| 79 |         }
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| 80 |         static inline void ?{}( $mgd_link(tE) &this, void * terminator ) {
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| 81 |                 (this.elem){ 0p };
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| 82 |                 (this.terminator){ terminator };
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| 83 |                 (this.is_terminator){ 1 };
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| 84 |         }
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| 85 |         static inline void ?=?( $mgd_link(tE) &this, tE* elem ) {
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| 86 |                 this.elem = elem ;
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| 87 |                 this.terminator = 0p;
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| 88 |                 this.is_terminator = 0;
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| 89 |         }
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| 90 |         static inline void ?=?( $mgd_link(tE) &this, void * terminator ) {
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| 91 |                 this.elem = 0p;
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| 92 |                 this.terminator = terminator;
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| 93 |                 this.is_terminator = 1;
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| 94 |         }
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| 95 |         struct $dlinks {
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| 96 |                 // containing item is not listed
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| 97 |                 // iff
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| 98 |                 // links have (elem == 0p && terminator == 0p)
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| 99 |                 $mgd_link(tE) next;
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| 100 |                 $mgd_link(tE) prev;
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| 101 |         };
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| 102 |         static inline void ?{}( $dlinks(tE) &this ) {
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| 103 |                 (this.next){ (tE *)0p };
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| 104 |                 (this.prev){ (tE *)0p };
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| 105 |         }
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| 106 | }
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| 107 | 
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| 108 | #define DLISTED_MGD_EXPL_IN(STRUCT, LIST_SUF) \
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| 109 |   $dlinks(STRUCT) $links_ ## LIST_SUF;
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| 110 | 
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| 111 | #define DLISTED_MGD_EXPL_OUT(STRUCT, LIST_SUF) \
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| 112 |   __DLISTED_MGD_JUSTEXPL(STRUCT, in_##LIST_SUF, STRUCT ## _in_ ## LIST_SUF) \
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| 113 |   __DLISTED_MGD_COMMON(STRUCT, STRUCT##_in_##LIST_SUF,  $links_ ## LIST_SUF)
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| 114 | 
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| 115 | #define DLISTED_MGD_IMPL_IN(STRUCT) \
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| 116 |   $dlinks(STRUCT) $links;
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| 117 | 
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| 118 | #define DLISTED_MGD_IMPL_OUT(STRUCT) \
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| 119 |   __DLISTED_MGD_JUSTIMPL(STRUCT) \
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| 120 |   __DLISTED_MGD_COMMON(STRUCT, STRUCT, $links)
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| 121 | 
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| 122 | trait $dlistable(Tnode &, Telem &) {
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| 123 |         $mgd_link(Telem) & $prev_link(Tnode &);
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| 124 |         $mgd_link(Telem) & $next_link(Tnode &);
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| 125 |         Telem& $tempcv_n2e(Tnode &);
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| 126 |         Tnode& $tempcv_e2n(Telem &);
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| 127 | 
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| 128 |         Telem& ?`next(Tnode &);
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| 129 |         Telem& ?`prev(Tnode &);
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| 130 | };
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| 131 | 
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| 132 | forall (Tnode &, Telem & | $dlistable(Tnode, Telem)) {
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| 133 | 
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| 134 |         // implemented as a sentinel item in an underlying cicrular list
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| 135 |         // theList.$links.next is first
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| 136 |         // theList.$links.prev is last
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| 137 |         // note this allocation preserves prev-next composition as an identity
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| 138 |         struct dlist {
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| 139 |                 $dlinks(Telem) $links;
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| 140 |         };
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| 141 | 
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| 142 |         // an empty dlist
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| 143 |         // links refer to self, making a tight circle
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| 144 |         static inline void ?{}( dlist(Tnode, Telem) & this ) {
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| 145 |                 $mgd_link(Telem) selfRef = (void *) &this;
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| 146 |                 ( this.$links ) { selfRef, selfRef };
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| 147 |         }
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| 148 | 
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| 149 |         static inline Telem & ?`first( dlist(Tnode, Telem) &l ) {
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| 150 |                 return * l.$links.next.elem;
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| 151 |         }
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| 152 | 
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| 153 |         static inline Telem & ?`last( dlist(Tnode, Telem) &l ) {
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| 154 |                 return * l.$links.prev.elem;
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| 155 |         }
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| 156 | 
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| 157 |         #if !defined(NDEBUG) && (defined(__CFA_DEBUG__) || defined(__CFA_VERIFY__))
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| 158 |         static bool $validate_fwd( dlist(Tnode, Telem) & this ) {
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| 159 |                 Tnode * it = & $tempcv_e2n( this`first );
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| 160 |                 if (!it) return (& this`last == 0p);
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| 161 | 
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| 162 |                 while( $next_link(*it).elem ) {
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| 163 |                         it = & $tempcv_e2n( * $next_link(*it).elem );
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| 164 |                 }
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| 165 | 
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| 166 |                 return ( it == & $tempcv_e2n( this`last ) ) &&
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| 167 |                            ( $next_link(*it).is_terminator ) &&
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| 168 |                            ( ((dlist(Tnode, Telem)*)$next_link(*it).terminator) == &this );
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| 169 |         }
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| 170 |         static bool $validate_rev( dlist(Tnode, Telem) & this ) {
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| 171 |                 Tnode * it = & $tempcv_e2n( this`last );
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| 172 |                 if (!it) return (& this`first == 0p);
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| 173 | 
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| 174 |                 while( $prev_link(*it).elem ) {
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| 175 |                         it = & $tempcv_e2n( * $prev_link(*it).elem );
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| 176 |                 }
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| 177 | 
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| 178 |                 return ( it == & $tempcv_e2n( this`first ) ) &&
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| 179 |                            ( $prev_link(*it).is_terminator ) &&
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| 180 |                            ( ((dlist(Tnode, Telem)*)$prev_link(*it).terminator) == &this );
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| 181 |         }
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| 182 |         static bool validate( dlist(Tnode, Telem) & this ) {
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| 183 |                 return $validate_fwd(this) && $validate_rev(this);
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| 184 |         }
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| 185 |         #endif
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| 186 | 
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| 187 |         static inline void insert_after(Tnode &list_pos, Telem &to_insert) {
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| 188 |                 verify (&list_pos != 0p);
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| 189 |                 verify (&to_insert != 0p);
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| 190 |                 Tnode &singleton_to_insert = $tempcv_e2n(to_insert);
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| 191 |                 verify($prev_link(singleton_to_insert).elem == 0p);
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| 192 |                 verify($next_link(singleton_to_insert).elem == 0p);
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| 193 |                 $prev_link(singleton_to_insert) = & $tempcv_n2e(list_pos);
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| 194 |                 $next_link(singleton_to_insert) = $next_link(list_pos);
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| 195 |                 if ($next_link(list_pos).is_terminator) {
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| 196 |                         dlist(Tnode, Telem) *list = ( dlist(Tnode, Telem) * ) $next_link(list_pos).terminator;
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| 197 |                         $dlinks(Telem) *list_links = & list->$links;
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| 198 |                         $mgd_link(Telem) *list_last = & list_links->prev;
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| 199 |                         *list_last = &to_insert;
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| 200 |                 } else {
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| 201 |                         Telem *list_pos_next = $next_link(list_pos).elem;
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| 202 |                         if (list_pos_next) {
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| 203 |                                 Tnode & lpn_inlist = $tempcv_e2n(*list_pos_next);
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| 204 |                                 $prev_link(lpn_inlist) = &to_insert;
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| 205 |                         }
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| 206 |                 }
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| 207 |                 $next_link(list_pos) = &to_insert;
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| 208 |         }
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| 209 | 
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| 210 |         static inline void insert_before(Tnode &list_pos, Telem &to_insert) {
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| 211 |                 verify (&list_pos != 0p);
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| 212 |                 verify (&to_insert != 0p);
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| 213 |                 Tnode &singleton_to_insert = $tempcv_e2n(to_insert);
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| 214 |                 verify($prev_link(singleton_to_insert).elem == 0p);
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| 215 |                 verify($next_link(singleton_to_insert).elem == 0p);
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| 216 |                 $next_link(singleton_to_insert) = & $tempcv_n2e(list_pos);
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| 217 |                 $prev_link(singleton_to_insert) = $prev_link(list_pos);
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| 218 |                 if ($prev_link(list_pos).is_terminator) {
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| 219 |                         dlist(Tnode, Telem) *list = ( dlist(Tnode, Telem) * ) $prev_link(list_pos).terminator;
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| 220 |                         $dlinks(Telem) *list_links = & list->$links;
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| 221 |                         $mgd_link(Telem) *list_first = & list_links->next;
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| 222 |                         *list_first = &to_insert;
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| 223 |                 } else {
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| 224 |                         Telem *list_pos_prev = $prev_link(list_pos).elem;
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| 225 |                         if (list_pos_prev) {
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| 226 |                                 Tnode & lpp_inlist = $tempcv_e2n(*list_pos_prev);
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| 227 |                                 $next_link(lpp_inlist) = &to_insert;
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| 228 |                         }
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| 229 |                 }
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| 230 |                 $prev_link(list_pos) = &to_insert;
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| 231 |         }
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| 232 | 
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| 233 |     static inline void insert_first(dlist(Tnode, Telem) &list, Telem &to_insert) {
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| 234 |                 verify (&list != 0p);
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| 235 |                 verify (&to_insert != 0p);
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| 236 |                 Tnode &singleton_to_insert = $tempcv_e2n(to_insert);
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| 237 |                 verify($prev_link(singleton_to_insert).elem == 0p);
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| 238 |                 verify($next_link(singleton_to_insert).elem == 0p);
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| 239 | 
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| 240 |                 $prev_link(singleton_to_insert) = (void*) &list;
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| 241 |                 $next_link(singleton_to_insert) = list.$links.next;
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| 242 | 
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| 243 |                 $dlinks(Telem) *listLinks = & list.$links;
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| 244 |                 if (listLinks->next.is_terminator) {
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| 245 |                         $mgd_link(Telem) * listPrevReference = & listLinks->prev;
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| 246 |                         *listPrevReference = &to_insert;
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| 247 |                 } else {
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| 248 |                         Tnode & next_inlist = $tempcv_e2n(*list.$links.next.elem);
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| 249 |                         $prev_link(next_inlist) = &to_insert;
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| 250 |                 }
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| 251 |                 $mgd_link(Telem) * listNextReference = & listLinks->next;
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| 252 |                 *listNextReference = &to_insert;
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| 253 |         }
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| 254 | 
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| 255 |     static inline void insert_last(dlist(Tnode, Telem) &list, Telem &to_insert) {
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| 256 |                 verify (&list != 0p);
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| 257 |                 verify (&to_insert != 0p);
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| 258 |                 Tnode &singleton_to_insert = $tempcv_e2n(to_insert);
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| 259 |                 verify($next_link(singleton_to_insert).elem == 0p);
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| 260 |                 verify($prev_link(singleton_to_insert).elem == 0p);
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| 261 | 
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| 262 |                 $next_link(singleton_to_insert) = (void*) &list;
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| 263 |                 $prev_link(singleton_to_insert) = list.$links.prev;
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| 264 | 
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| 265 |                 $dlinks(Telem) *listLinks = & list.$links;
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| 266 |                 if (listLinks->prev.is_terminator) {
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| 267 |                         $mgd_link(Telem) * listNextReference = & listLinks->next;
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| 268 |                         *listNextReference = &to_insert;
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| 269 |                 } else {
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| 270 |                         Tnode & prev_inlist = $tempcv_e2n(*list.$links.prev.elem);
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| 271 |                         $next_link(prev_inlist) = &to_insert;
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| 272 |                 }
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| 273 |                 $mgd_link(Telem) * listPrevReference = & listLinks->prev;
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| 274 |                 *listPrevReference = &to_insert;
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| 275 |         }
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| 276 | 
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| 277 |     static inline void remove(Tnode &list_pos) {
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| 278 |                 verify( &list_pos != 0p );
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| 279 | 
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| 280 |                 $mgd_link(Telem) &incoming_from_prev = *0p;
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| 281 |                 $mgd_link(Telem) &incoming_from_next = *0p;
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| 282 | 
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| 283 |                 if ( $prev_link(list_pos).is_terminator ) {
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| 284 |                         dlist(Tnode, Telem) * tgt_before = ( dlist(Tnode, Telem) * ) $prev_link(list_pos).terminator;
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| 285 |                         $dlinks(Telem) * links_before = & tgt_before->$links;
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| 286 |                         &incoming_from_prev = & links_before->next;
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| 287 |                 } else if ($prev_link(list_pos).elem) {
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| 288 |                         Telem * tgt_before = $prev_link(list_pos).elem;
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| 289 |                         Tnode & list_pos_before = $tempcv_e2n(*tgt_before);
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| 290 |                         &incoming_from_prev = & $next_link(list_pos_before);
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| 291 |                 }
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| 292 | 
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| 293 |                 if ( $next_link(list_pos).is_terminator ) {
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| 294 |                         dlist(Tnode, Telem) * tgt_after = ( dlist(Tnode, Telem) * ) $next_link(list_pos).terminator;
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| 295 |                         $dlinks(Telem) * links_after = & tgt_after->$links;
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| 296 |                         &incoming_from_next = & links_after->prev;
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| 297 |                 } else if ($next_link(list_pos).elem) {
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| 298 |                         Telem * tgt_after  = $next_link(list_pos).elem;
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| 299 |                         Tnode & list_pos_after  = $tempcv_e2n(*tgt_after );
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| 300 |                         &incoming_from_next = & $prev_link(list_pos_after );
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| 301 |                 }
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| 302 | 
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| 303 |                 if (& incoming_from_prev) {
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| 304 |                         incoming_from_prev = $next_link(list_pos);
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| 305 |                 }
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| 306 |                 if (& incoming_from_next) {
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| 307 |                         incoming_from_next = $prev_link(list_pos);
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| 308 |                 }
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| 309 | 
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| 310 |                 $next_link(list_pos) = (Telem*) 0p;
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| 311 |                 $prev_link(list_pos) = (Telem*) 0p;
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| 312 |         }
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| 313 | 
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| 314 |         static inline bool ?`is_empty(dlist(Tnode, Telem) &list) {
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| 315 |                 verify( &list != 0p );
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| 316 |                 $dlinks(Telem) *listLinks = & list.$links;
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| 317 |                 if (listLinks->next.is_terminator) {
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| 318 |                         verify(listLinks->prev.is_terminator);
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| 319 |                         verify(listLinks->next.terminator);
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| 320 |                         verify(listLinks->prev.terminator);
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| 321 |                         return true;
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| 322 |                 } else {
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| 323 |                         verify(!listLinks->prev.is_terminator);
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| 324 |                         verify(listLinks->next.elem);
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| 325 |                         verify(listLinks->prev.elem);
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| 326 |                         return false;
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| 327 |                 }
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| 328 |         }
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| 329 | 
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| 330 |         static inline Telem & pop_first(dlist(Tnode, Telem) &list) {
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| 331 |                 verify( &list != 0p );
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| 332 |                 verify( !list`is_empty );
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| 333 |                 $dlinks(Telem) *listLinks = & list.$links;
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| 334 |                 Telem & first = *listLinks->next.elem;
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| 335 |                 Tnode & list_pos_first  = $tempcv_e2n( first );
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| 336 |                 remove(list_pos_first);
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| 337 |                 return first;
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| 338 |         }
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| 339 | 
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| 340 |         static inline Telem & pop_last(dlist(Tnode, Telem) &list) {
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| 341 |                 verify( &list != 0p );
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| 342 |                 verify( !list`is_empty );
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| 343 |                 $dlinks(Telem) *listLinks = & list.$links;
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| 344 |                 Telem & last = *listLinks->prev.elem;
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| 345 |                 Tnode & list_pos_last  = $tempcv_e2n( last );
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| 346 |                 remove(list_pos_last);
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| 347 |                 return last;
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| 348 |         }
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| 349 | 
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| 350 | }
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| 351 | 
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