99 lines
2.1 KiB
Go
99 lines
2.1 KiB
Go
// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
|
|
// All rights reserved.
|
|
|
|
// operator-prod.go
|
|
package expr
|
|
|
|
import (
|
|
"errors"
|
|
"strings"
|
|
)
|
|
|
|
//-------- multiply term
|
|
|
|
func newMultiplyTerm(tk *Token) (inst *term) {
|
|
return &term{
|
|
tk: *tk,
|
|
class: classOperator,
|
|
kind: kindUnknown,
|
|
children: make([]*term, 0, 2),
|
|
position: posInfix,
|
|
priority: priProduct,
|
|
evalFunc: evalMultiply,
|
|
}
|
|
}
|
|
|
|
func evalMultiply(ctx exprContext, self *term) (v any, err error) {
|
|
var leftValue, rightValue any
|
|
|
|
if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
|
|
return
|
|
}
|
|
|
|
if isString(leftValue) && isInteger(rightValue) {
|
|
s, _ := leftValue.(string)
|
|
n, _ := rightValue.(int64)
|
|
v = strings.Repeat(s, int(n))
|
|
} else if isNumber(leftValue) && isNumber(rightValue) {
|
|
if isFloat(leftValue) || isFloat(rightValue) {
|
|
v = numAsFloat(leftValue) * numAsFloat(rightValue)
|
|
} else {
|
|
leftInt, _ := leftValue.(int64)
|
|
rightInt, _ := rightValue.(int64)
|
|
v = leftInt * rightInt
|
|
}
|
|
} else {
|
|
err = self.errIncompatibleTypes(leftValue, rightValue)
|
|
}
|
|
return
|
|
}
|
|
|
|
//-------- divide term
|
|
|
|
func newDivideTerm(tk *Token) (inst *term) {
|
|
return &term{
|
|
tk: *tk,
|
|
class: classOperator,
|
|
kind: kindUnknown,
|
|
children: make([]*term, 0, 2),
|
|
position: posInfix,
|
|
priority: priProduct,
|
|
evalFunc: evalDivide,
|
|
}
|
|
}
|
|
|
|
func evalDivide(ctx exprContext, self *term) (v any, err error) {
|
|
var leftValue, rightValue any
|
|
|
|
if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
|
|
return
|
|
}
|
|
|
|
if isNumber(leftValue) && isNumber(rightValue) {
|
|
if isFloat(leftValue) || isFloat(rightValue) {
|
|
d := numAsFloat(rightValue)
|
|
if d == 0.0 {
|
|
err = errors.New("division by zero")
|
|
} else {
|
|
v = numAsFloat(leftValue) / d
|
|
}
|
|
} else {
|
|
leftInt, _ := leftValue.(int64)
|
|
if rightInt, _ := rightValue.(int64); rightInt == 0 {
|
|
err = errors.New("division by zero")
|
|
} else {
|
|
v = leftInt / rightInt
|
|
}
|
|
}
|
|
} else {
|
|
err = self.errIncompatibleTypes(leftValue, rightValue)
|
|
}
|
|
return
|
|
}
|
|
|
|
// init
|
|
func init() {
|
|
registerTermConstructor(SymStar, newMultiplyTerm)
|
|
registerTermConstructor(SymSlash, newDivideTerm)
|
|
}
|