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Defer

Defer[expr]
yields an object that displays as the unevaluated form of expr, but that is evaluated if it is explicitly given as Mathematica input.
MORE INFORMATION
  • Defer[expr] returns an object that remains unchanged until it is explicitly supplied as Mathematica input and evaluated using Shift+Enter, Evaluate in Place, etc.
  • Defer gives an object whose evaluation is merely deferred until it is explicitly given as Mathematica input; HoldForm gives an object that is never evaluated.
  • If an object contains several levels of nested Defer constructs, one level is removed each time the object is evaluated as Mathematica input.
EXAMPLESCLOSE ALL
Basic Examples   (2)
By default, arguments are evaluated:
Use Defer to display an unevaluated form:
Copy the previous output and evaluate:
Use Defer to create cells with unevaluated contents:
By default, arguments are evaluated:
In[1]:=
Click for copyable input
Out[1]=
Use Defer to display an unevaluated form:
In[2]:=
Click for copyable input
Out[2]=
Copy the previous output and evaluate:
In[3]:=
Click for copyable input
Out[3]=
 
Use Defer to create cells with unevaluated contents:
In[1]:=
Click for copyable input
In[2]:=
Click for copyable input
In[3]:=
Click for copyable input
In[4]:=
Click for copyable input
In[5]:=
Click for copyable input
In[6]:=
Click for copyable input
Properties & Relations   (1)
Use HoldForm to display in unevaluated form:
Copy the output and evaluate; the result stays unevaluated:
Use ReleaseHold to force evaluation of the result:
Use Defer to display in unevaluated form:
Copy the output and evaluate:
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