expression EL表达式

项目地址：go-expression

目前发布初始版本，欢迎体验。

Install

go get github.com/heartlhj/go-expression

功能

• 字符串的提取和比较

	context := spel.StandardEvaluationContext{}
	m := make(map[string]interface{})
	m["name"] = "lisi"
	m["age"] = 18
	context.SetVariables(m)
	parser := SpelExpressionParser{}
	expressionString := "#name=='lisi'"
	//expressionString := "#name" //返回lisi
	valueContext := parser.ParseExpression(expressionString).GetValueContext(&context)

• 数字比较，支持int和 float64

	context := spel.StandardEvaluationContext{}
	m := make(map[string]interface{})
	m["name"] = "lisi"
	m["age"] = 18
	context.SetVariables(m)
	parser := SpelExpressionParser{}
	expressionString := "#age>=10"
	valueContext := parser.ParseExpression(expressionString).GetValueContext(&context)

float64比较

    context := spel.StandardEvaluationContext{}
	m := make(map[string]interface{})
	var ageFloat float64
	ageFloat = 10
	m["num"] = ageFloat
	context.SetVariables(m)
	parser := SpelExpressionParser{}
	expressionString := "#num>=9f"
	valueContext := parser.ParseExpression(expressionString).GetValueContext(&context)

• 与（&&）或 （||）操作

    context := spel.StandardEvaluationContext{}
	m := make(map[string]interface{})
	m["name"] = "lisi"
	m["age"] = 18
	context.SetVariables(m)
	parser := SpelExpressionParser{}
	expressionString := "#name=='lisi' && #age>=3"
	valueContext := parser.ParseExpression(expressionString).GetValueContext(&context)

• 复合结构，迭代提取

	context := spel.StandardEvaluationContext{}
	context.AddPropertyAccessor(spel.MapAccessor{})
	m := make(map[string]interface{})
	m["name"] = "lisi"
	m["age"] = 18
	m1 := make(map[string]interface{})
	m2 := make(map[string]interface{})
	m2["num"] = 12
	m1["code"] = m2
	m["order"] = m1
	context.SetVariables(m)
	parser := SpelExpressionParser{}
	expressionString := "#order.code.num==12"
	valueContext := parser.ParseExpression(expressionString).GetValueContext(&context)

• 数组和切片提取

	context := spel.StandardEvaluationContext{}
	context.AddPropertyAccessor(spel.MapAccessor{})
	m := make(map[string]interface{})
	m["name"] = "lisi"
	m["age"] = 18
	m1 := make(map[string]interface{})
	//切片
	//orders := make([]Order, 2)
	//数组
	orders := [2]Order{}
	orders[0] = Order{name: "lisi", age: 12}
	orders[1] = Order{name: "wang", age: 24}
	m1["code"] = orders
	m["order"] = m1
	context.SetVariables(m)
	parser := SpelExpressionParser{}
	expressionString := "#order.code[0].name=='lisi'"
	valueContext := parser.ParseExpression(expressionString).GetValueContext(&context)