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<head><title>globalAssignFunction -- the standard method for the global assignment hook</title>
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<div><h1>globalAssignFunction -- the standard method for the global assignment hook</h1>
<div class="single"><h2>Description</h2>
<div><tt>globalAssignFunction</tt> -- the standard function that can be used as a method for <a href="___Global__Assign__Hook.html" title="hook for assignment to global variables">GlobalAssignHook</a> so that certain types of things, when assigned to a global variable, will acquire the name of the global variable as their name. The companion function <a href="_global__Release__Function.html" title="the standard method for the global variable release hook">globalReleaseFunction</a> is used to release the name when the global variable gets reassigned.<p/>
Another thing done by this function is to apply <a href="_use.html" title="install or activate object">use</a> to the thing. This is used for polynomial rings to assign values to the symbols representing the variables (indeterminates) in the ring.<p/>
<table class="examples"><tr><td><pre>i1 : X = new Type of MutableHashTable
o1 = X
o1 : Type</pre>
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<tr><td><pre>i2 : x = new X
o2 = X{}
o2 : X</pre>
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<tr><td><pre>i3 : X.GlobalAssignHook = globalAssignFunction
o3 = globalAssignFunction
o3 : FunctionClosure</pre>
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<tr><td><pre>i4 : X.GlobalReleaseHook = globalReleaseFunction
o4 = globalReleaseFunction
o4 : FunctionClosure</pre>
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<tr><td><pre>i5 : x' = new X
o5 = x'
o5 : X</pre>
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<tr><td><pre>i6 : t = {x,x'}
o6 = {X{}, x'}
o6 : List</pre>
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<tr><td><pre>i7 : x = x' = 44
o7 = 44</pre>
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<tr><td><pre>i8 : t
o8 = {X{}, X{}}
o8 : List</pre>
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<tr><td><pre>i9 : code globalAssignFunction
o9 = /builddir/build/BUILD/Macaulay2-1.3.1-r10737/Macaulay2/d/startup.m2.in:211:35-215:15: --source code:
globalAssignFunction = (X,x) -> (
if not instance(X,Symbol) then error("globalAssignFunction: expected a symbol: ", toString X);
if not hasAttribute(x,ReverseDictionary) then setAttribute(x,ReverseDictionary,X);
use x;
);</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_symbol.html" title="get a symbol">symbol</a> -- get a symbol</span></li>
<li><span><a href="___Self__Initializing__Type.html" title="the class of all self initializing types">SelfInitializingType</a> -- the class of all self initializing types</span></li>
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