/usr/share/gap/lib/wpobj.gi is in gap-libs 4r7p5-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 | #############################################################################
##
#W wpobj.gi GAP library Steve Linton
##
##
#Y Copyright (C) 1997,
#Y (C) 1998 School Math and Comp. Sci., University of St Andrews, Scotland
#Y Copyright (C) 2002 The GAP Group
##
## This file contains the implementations for weak pointer objects
##
#############################################################################
##
#M <wp> [<pos>] access function for weak pointer objects
##
## We cannot use the kernel function directly, as it returns fail for unbound
## see comments in wpobj.gd for the reason.
##
InstallMethod(\[\],
"method for a weak pointer object",
true,
[ IsWeakPointerObject, IsPosInt ],
0,
function( wp, pos)
local elm;
elm := ElmWPObj(wp, pos);
if elm <> fail or IsBoundElmWPObj(wp,pos) then
return elm;
else
Error("<wpobj>[<pos>] must have a value.");
fi;
end);
#############################################################################
##
#M <wp> [<pos>] := <obj> weak pointer object member assignment
##
InstallMethod(\[\]\:\=,
"method for a weak pointer object",
true,
[ IsWeakPointerObject and IsMutable, IsPosInt, IsObject ],
0,
SetElmWPObj);
#############################################################################
##
#M Length( <wp> ) note that the answer may not stay valid
##
InstallMethod(Length,
"method for a weak pointer object",
true,
[ IsWeakPointerObject ],
0,
LengthWPObj);
#############################################################################
##
#M IsBound(<wp>[<pos>]) note that the answer may not stay valid
##
InstallMethod(IsBound\[\],
"method for a weak pointer object",
true,
[ IsWeakPointerObject, IsPosInt ],
0,
IsBoundElmWPObj);
#############################################################################
##
#M Unbind(<wp>[<pos>])
##
InstallMethod(Unbind\[\],
"method for a weak pointer object",
true,
[ IsWeakPointerObject and IsMutable, IsPosInt ],
0,
UnbindElmWPObj);
#############################################################################
##
#M Print method, ~ is not supported, so self-referential weak pointer
## objects cannot be printed
##
InstallMethod(PrintObj,
"method for a weak pointer object",
true,
[ IsWeakPointerObject ],
0,
function(wp)
local i,l,x;
Print("WeakPointerObj( [ ");
l := Length(wp);
if l <> 0 then
x := ElmWPObj(wp,1);
if x <> fail or IsBoundElmWPObj(wp,1) then
PrintObj(x);
fi;
for i in [2..l] do
Print(", ");
x := ElmWPObj(wp,i);
if x <> fail or IsBoundElmWPObj(wp,i) then
PrintObj(x);
fi;
od;
fi;
Print(" ] )");
end);
#############################################################################
##
#M View method, ~ is not supported, so self-referential weak pointer
## objects cannot be printed
##
InstallMethod(ViewObj,
"method for a weak pointer object",
true,
[ IsWeakPointerObject ],
0,
function(wp)
local i,l,x;
Print("WeakPointerObj( [ ");
l := Length(wp);
if l <> 0 then
x := ElmWPObj(wp,1);
if x <> fail or IsBoundElmWPObj(wp,1) then
ViewObj(x);
fi;
for i in [2..l] do
Print(", ");
x := ElmWPObj(wp,i);
if x <> fail or IsBoundElmWPObj(wp,i) then
ViewObj(x);
fi;
od;
fi;
Print(" ] )");
end);
#############################################################################
##
#M ShallowCopy(<wp>)
##
## Note that we do not use wp[i] access (see wpobj.gd for explanation)
##
InstallMethod(ShallowCopy,
"method for a weak pointer object",
true,
[ IsWeakPointerObject ],
0,
function(wp)
local w,i,l,x;
w := WeakPointerObj([]);
l := Length(wp);
for i in [1..l] do
x := ElmWPObj(wp,i);
if x <> fail or IsBound(wp[i]) then
w[i] := x;
fi;
od;
return w;
end);
#############################################################################
##
#E
|