func_lsh.go

package fgbase

import (
	"reflect"
)

func lshFire2(a, b interface{}) interface{} {

	switch a.(type) {
	case uint8:
		{
			return a.(uint8) << b.(uint8)
		}
	case uint16:
		{
			return a.(uint16) << b.(uint16)
		}
	case uint32:
		{
			return a.(uint32) << b.(uint32)
		}
	case uint64:
		{
			return a.(uint64) << b.(uint64)
		}
	case uint:
		{
			return a.(uint) << b.(uint)
		}
	default:
		{
			return nil
		}
	}
}

// Left shift primitive
func lshFire(n *Node) error {

	a := n.Srcs[0]
	b := n.Srcs[1]
	x := n.Dsts[0]

	aTmp, bTmp, same := Promote(n, a.SrcGet(), b.SrcGet())

	if !same {
		n.LogError("incompatible types for left shift (%v<<%v)", reflect.TypeOf(a.Val), reflect.TypeOf(b.Val))
		x.DstPut(nil)
	} else {
		x.DstPut(lshFire2(aTmp, bTmp))
	}
	return nil
}

// FuncLsh left shifts a value(x = a << b).
func FuncLsh(a, b, x Edge) Node {

	node := MakeNode("lsh", []*Edge{&a, &b}, []*Edge{&x}, nil, lshFire)
	return node
}