operator.type {operator.tools} | R Documentation |
Return the type for an operator.
Description
Given an operator or its name/symbol, return the type of operator.
Usage
operator.type(op)
Arguments
op |
An operator either as a name/symbol or function. |
Details
The operator is first checked against all operators that have been
registered with the setOperator
command. If there is a match,
its type is returned. If no matching operator is found, op
is matched
against unregistered operators that have been defined with the
%any%
-syntax. If a match is found, UNREGISTERED is returned.
The list of operators are maintained in .Options\$operators
and be
altered suing the setOperator
command.
Value
A character
value.
For registered operators, the registered type is returned. For Base R
operators, the types come from Syntax
.
For operators defined with the %any%
-syntax but, not registered using
setOperator
, "UNREGISTERED" is returned.
NULL is returned otherwise.
Author(s)
Christopher Brown
See Also
operators
, setOperator
. Syntax
Examples
## Not run:
operator.type( `+` )
operator.type( `<=` )
e <- quote( A +B )
operator.type( e[[1]] )
operator.type( as.name('+') )
## End(Not run)