BlankSequence

__ (two _ characters) or BlankSequence[]

is a pattern object that can stand for any sequence of one or more Wolfram Language expressions.

__h or BlankSequence[h]

can stand for any sequence of one or more expressions, all of which have head h.

Examples

Basic Examples  (3)

A function definition that works with any nonzero number of arguments:

In[1]:=
Click for copyable input
In[2]:=
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Out[2]=

A function definition that works with any nonzero number of real arguments:

In[1]:=
Click for copyable input
In[2]:=
Click for copyable input
Out[2]=

A function definition for a symbol followed by any nonzero number of integer arguments:

In[1]:=
Click for copyable input
In[2]:=
Click for copyable input
Out[2]=

See Also

BlankNullSequence  Blank  OptionsPattern  Repeated  Sequence  StringExpression  Nothing  SequencePosition

Tutorials

Introduced in 1988
(1.0)