with the new operators '<+' and '+>' respectively. '<<' and '>>' are now used only for left and right binary shit respectively. Further, their priority has been increased moving them to a higher priority than that of the assignment operator.
92 lines
2.0 KiB
Go
92 lines
2.0 KiB
Go
// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
|
|
// All rights reserved.
|
|
|
|
// operator-insert.go
|
|
package expr
|
|
|
|
//-------- prepend term
|
|
|
|
func newPrependTerm(tk *Token) (inst *term) {
|
|
return &term{
|
|
tk: *tk,
|
|
children: make([]*term, 0, 2),
|
|
position: posInfix,
|
|
priority: priInsert,
|
|
evalFunc: evalPrepend,
|
|
}
|
|
}
|
|
|
|
func newAppendTerm(tk *Token) (inst *term) {
|
|
return &term{
|
|
tk: *tk,
|
|
children: make([]*term, 0, 2),
|
|
position: posInfix,
|
|
priority: priInsert,
|
|
evalFunc: evalAppend,
|
|
}
|
|
}
|
|
|
|
func evalPrepend(ctx ExprContext, opTerm *term) (v any, err error) {
|
|
var leftValue, rightValue any
|
|
|
|
if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
|
|
return
|
|
}
|
|
|
|
if IsList(rightValue) {
|
|
list, _ := rightValue.(*ListType)
|
|
newList := append(ListType{leftValue}, *list...)
|
|
v = &newList
|
|
if opTerm.children[1].symbol() == SymVariable {
|
|
ctx.UnsafeSetVar(opTerm.children[1].source(), v)
|
|
}
|
|
} else {
|
|
err = opTerm.errIncompatibleTypes(leftValue, rightValue)
|
|
}
|
|
return
|
|
}
|
|
|
|
func evalAppend(ctx ExprContext, opTerm *term) (v any, err error) {
|
|
var leftValue, rightValue any
|
|
|
|
if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
|
|
return
|
|
}
|
|
|
|
if IsList(leftValue) {
|
|
list, _ := leftValue.(*ListType)
|
|
newList := append(*list, rightValue)
|
|
v = &newList
|
|
if opTerm.children[0].symbol() == SymVariable {
|
|
ctx.UnsafeSetVar(opTerm.children[0].source(), v)
|
|
}
|
|
} else {
|
|
err = opTerm.errIncompatibleTypes(leftValue, rightValue)
|
|
}
|
|
return
|
|
}
|
|
|
|
// func evalAssignAppend(ctx ExprContext, self *term) (v any, err error) {
|
|
// var leftValue, rightValue any
|
|
|
|
// if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
|
|
// return
|
|
// }
|
|
|
|
// if IsList(leftValue) {
|
|
// list, _ := leftValue.(*ListType)
|
|
// newList := append(*list, rightValue)
|
|
// v = &newList
|
|
// if
|
|
// } else {
|
|
// err = self.errIncompatibleTypes(leftValue, rightValue)
|
|
// }
|
|
// return
|
|
// }
|
|
|
|
// init
|
|
func init() {
|
|
registerTermConstructor(SymPlusGreater, newPrependTerm)
|
|
registerTermConstructor(SymLessPlus, newAppendTerm)
|
|
}
|