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Stephen Wolfram
SEARCH MATHEMATICA 8 DOCUMENTATION
THIS IS DOCUMENTATION FOR AN OBSOLETE PRODUCT.
SEE THE
DOCUMENTATION CENTER
FOR THE LATEST INFORMATION.
Mathematica
>
Rules
>
Built-in
Mathematica
Symbol
Applying Transformation Rules
Some General Notations and Conventions
Tutorials »
|
Rule
Replace
SetDelayed
See Also »
|
Language Overview
Options Management
Rules
Rules & Patterns
Scoping Constructs
Mathematica Syntax
More About »
RuleDelayed
lhs
:>
rhs
or
lhs
⧴rhs
represents a rule that transforms
lhs
to
rhs
, evaluating
rhs
only after the rule is used.
MORE INFORMATION
The character
:>
can be entered as
Esc
:>
Esc
or
\[RuleDelayed]
.
RuleDelayed
has the attribute
HoldRest
.
You can apply rules using
Replace
.
The assignment
lhs
:=
rhs
specifies that the rule
lhs
:>
rhs
should be used whenever it applies.
You can use
Condition
to specify when a particular rule applies.
In
StandardForm
,
RuleDelayed
is printed using
:>
.
EXAMPLES
CLOSE ALL
Basic Examples
(1)
:> holds its right-hand side unevaluated:
In[1]:=
Out[1]=
The right-hand side is evaluated separately each time it is used:
In[2]:=
Out[2]=
Applications
(3)
Properties & Relations
(1)
SEE ALSO
Rule
Replace
SetDelayed
TUTORIALS
Applying Transformation Rules
Some General Notations and Conventions
MORE ABOUT
Language Overview
Options Management
Rules
Rules & Patterns
Scoping Constructs
Mathematica Syntax
New in 1 | Last modified in 3
© 2013 Wolfram Research, Inc.
EXAMPLES
Basic Examples 
Applications 