expr/operator-context.go

61 lines
1.5 KiB
Go

// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
// All rights reserved.
// operator-context-value.go
package expr
//-------- context term
func newContextTerm(tk *Token) (inst *term) {
return &term{
tk: *tk,
children: make([]*term, 0, 1),
position: posPrefix,
priority: priIncDec,
evalFunc: evalContextValue,
}
}
func evalContextValue(ctx ExprContext, opTerm *term) (v any, err error) {
var childValue any
var sourceCtx ExprContext
if len(opTerm.children) == 0 {
sourceCtx = ctx
} else if opTerm.children[0].symbol() == SymVariable && opTerm.children[0].source() == "global" {
sourceCtx = globalCtx
} else if childValue, err = opTerm.evalPrefix(ctx); err == nil {
if dc, ok := childValue.(*dataCursor); ok {
sourceCtx = dc.ctx
}
}
if sourceCtx != nil {
if formatter, ok := sourceCtx.(DictFormat); ok {
v = formatter.ToDict()
} else if formatter, ok := sourceCtx.(Formatter); ok {
v = formatter.ToString(0)
} else {
// keys := sourceCtx.EnumVars(func(name string) bool { return name[0] != '_' })
keys := sourceCtx.EnumVars(nil)
d := make(map[string]any)
for _, key := range keys {
d[key], _ = sourceCtx.GetVar(key)
}
keys = sourceCtx.EnumFuncs(func(name string) bool { return true })
for _, key := range keys {
d[key], _ = sourceCtx.GetFuncInfo(key)
}
v = d
}
} else {
err = opTerm.errIncompatibleType(childValue)
}
return
}
// init
func init() {
registerTermConstructor(SymDoubleDollar, newContextTerm)
}