// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
// All rights reserved.
// context.go
package expr
// ---- Function template
type FuncTemplate func(ctx ExprContext, name string, args []any) (result any, err error)
// ---- Functor interface
type Functor interface {
Invoke(ctx ExprContext, name string, args []any) (result any, err error)
}
type simpleFunctor struct {
f FuncTemplate
}
func newSimpleFunctor(f FuncTemplate) *simpleFunctor {
return &simpleFunctor{f: f}
}
func (functor *simpleFunctor) Invoke(ctx ExprContext, name string, args []any) (result any, err error) {
return functor.f(ctx, name, args)
}
func (functor *simpleFunctor) ToString(opt FmtOpt) string {
return "func() {<body>}"
}
// ---- Function Param Info
type ExprFuncParam interface {
Name() string
Type() string
IsOptional() bool
IsRepeat() bool
DefaultValue() any
}
// ---- Function Info
type ExprFunc interface {
Name() string
MinArgs() int
MaxArgs() int
Functor() Functor
Params() []ExprFuncParam
ReturnType() string
}
// ----Expression Context
type ExprContext interface {
Clone() ExprContext
GetVar(varName string) (value any, exists bool)
SetVar(varName string, value any)
UnsafeSetVar(varName string, value any)
EnumVars(func(name string) (accept bool)) (varNames []string)
EnumFuncs(func(name string) (accept bool)) (funcNames []string)
GetFuncInfo(name string) (item ExprFunc, exists bool)
Call(name string, args []any) (result any, err error)
// RegisterFunc(name string, f Functor, minArgs, maxArgs int)
RegisterFuncInfo(info ExprFunc)
RegisterFunc2(name string, f Functor, returnType string, param []ExprFuncParam) error
}