operator.tools (version 1.4.4)

operator.type: 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.

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.

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.

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)