33 lines
714 B
Go
33 lines
714 B
Go
|
package govaluate
|
||
|
|
||
|
import (
|
||
|
"errors"
|
||
|
)
|
||
|
|
||
|
/*
|
||
|
Parameters is a collection of named parameters that can be used by an EvaluableExpression to retrieve parameters
|
||
|
when an expression tries to use them.
|
||
|
*/
|
||
|
type Parameters interface {
|
||
|
|
||
|
/*
|
||
|
Get gets the parameter of the given name, or an error if the parameter is unavailable.
|
||
|
Failure to find the given parameter should be indicated by returning an error.
|
||
|
*/
|
||
|
Get(name string) (interface{}, error)
|
||
|
}
|
||
|
|
||
|
type MapParameters map[string]interface{}
|
||
|
|
||
|
func (p MapParameters) Get(name string) (interface{}, error) {
|
||
|
|
||
|
value, found := p[name]
|
||
|
|
||
|
if !found {
|
||
|
errorMessage := "No parameter '" + name + "' found."
|
||
|
return nil, errors.New(errorMessage)
|
||
|
}
|
||
|
|
||
|
return value, nil
|
||
|
}
|