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Blank (_)

_ or Blank[]
is a pattern object that can stand for any Mathematica expression.
_h or Blank[h]
can stand for any expression with head h.
  • The head h in _h cannot itself contain pattern objects.
EXAMPLESCLOSE ALL
Basic Examples   (2)
A pattern that matches any expression:
A pattern that matches any symbol:
A function definition that will take any single argument:
A function definition for integer arguments only:
A pattern that matches any expression:
In[1]:=
Click for copyable input
Out[1]=
A pattern that matches any symbol:
In[2]:=
Click for copyable input
Out[2]=
 
A function definition that will take any single argument:
In[1]:=
Click for copyable input
In[2]:=
Click for copyable input
Out[2]=
A function definition for integer arguments only:
In[3]:=
Click for copyable input
In[4]:=
Click for copyable input
Out[4]=
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