58 lines
1.1 KiB
Go
58 lines
1.1 KiB
Go
|
// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
|
||
|
|
// All rights reserved.
|
||
|
|
|
||
|
|
// operand-fraction.go
|
||
|
|
package expr
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"strings"
|
||
|
|
)
|
||
|
|
|
||
|
|
type fraction struct {
|
||
|
|
num, den int64
|
||
|
|
}
|
||
|
|
|
||
|
|
func (f *fraction) ToString(opt FmtOpt) string {
|
||
|
|
var sb strings.Builder
|
||
|
|
sb.WriteString(fmt.Sprintf("%d|%d", f.num, f.den))
|
||
|
|
return sb.String()
|
||
|
|
}
|
||
|
|
|
||
|
|
// -------- fraction term
|
||
|
|
func newFractionTerm(tk *Token) *term {
|
||
|
|
return &term{
|
||
|
|
tk: *tk,
|
||
|
|
parent: nil,
|
||
|
|
children: make([]*term, 0, 2),
|
||
|
|
position: posInfix,
|
||
|
|
priority: priFraction,
|
||
|
|
evalFunc: evalFraction,
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// -------- eval func
|
||
|
|
func evalFraction(ctx ExprContext, self *term) (v any, err error) {
|
||
|
|
var numValue, denValue any
|
||
|
|
var num, den int64
|
||
|
|
var ok bool
|
||
|
|
|
||
|
|
if numValue, denValue, err = self.evalInfix(ctx); err != nil {
|
||
|
|
return
|
||
|
|
}
|
||
|
|
if num, ok = numValue.(int64); !ok {
|
||
|
|
err = fmt.Errorf("numerator must be integer, got %T (%v)", numValue, numValue)
|
||
|
|
}
|
||
|
|
if den, ok = denValue.(int64); !ok {
|
||
|
|
err = fmt.Errorf("denominator must be integer, got %T (%v)", denValue, denValue)
|
||
|
|
}
|
||
|
|
|
||
|
|
v = &fraction{num, den}
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
// init
|
||
|
|
func init() {
|
||
|
|
registerTermConstructor(SymVertBar, newFractionTerm)
|
||
|
|
}
|