el

type Context struct {
	// Name of the currently processed field.
	Name string
	// Name of the currently processed field including type.
	LongName string
	// Current value of the currently processed filed.
	Val interface{}
	// All other tags of the currently processed field.
	Tags map[string]string
	// Currently processed struct.
	Struct interface{}
	// Extra context structure.
	Extra interface{}
	// Temporary partial result evaluated on the current substruct.
	Sub interface{}
}

type DefaultInterpreter struct {
	// Custom functions, available for use in EL expressions.
	Funcs use.FuncMap
	// Left delimiter for templates.
	LeftDelim string
	// Right delimiter for templates.
	RightDelim string
	// Automatically enclose passed expression into delimiters before
	// interpretation (if it is not already enclosed). This allows to pass
	// simplified expressions. For example, `atoi "42"` instead of
	// `{{atoi "42"}}`.
	AutoEnclose bool
}

type Interpreter interface {
	// Execute parses and executes expression with a given context.
	Execute(expression string, ctx *Context) (result interface{}, err error)
}