1#pragma once
2
3#include <mbgl/style/expression/expression.hpp>
4#include <mbgl/style/expression/parsing_context.hpp>
5#include <mbgl/style/conversion.hpp>
6
7#include <memory>
8#include <map>
9
10namespace mbgl {
11namespace style {
12namespace expression {
13
14class Let : public Expression {
15public:
16 using Bindings = std::map<std::string, std::shared_ptr<Expression>>;
17
18 Let(Bindings bindings_, std::unique_ptr<Expression> result_) :
19 Expression(Kind::Let, result_->getType()),
20 bindings(std::move(bindings_)),
21 result(std::move(result_))
22 {}
23
24 static ParseResult parse(const mbgl::style::conversion::Convertible&, ParsingContext&);
25
26 EvaluationResult evaluate(const EvaluationContext& params) const override;
27 void eachChild(const std::function<void(const Expression&)>&) const override;
28
29 bool operator==(const Expression& e) const override {
30 if (e.getKind() == Kind::Let) {
31 auto rhs = static_cast<const Let*>(&e);
32 return *result == *(rhs->result);
33 }
34 return false;
35 }
36
37 std::vector<optional<Value>> possibleOutputs() const override;
38
39 Expression* getResult() const {
40 return result.get();
41 }
42
43 mbgl::Value serialize() const override;
44 std::string getOperator() const override { return "let"; }
45private:
46 Bindings bindings;
47 std::unique_ptr<Expression> result;
48};
49
50class Var : public Expression {
51public:
52 Var(std::string name_, std::shared_ptr<Expression> value_) :
53 Expression(Kind::Var, value_->getType()),
54 name(std::move(name_)),
55 value(value_)
56 {}
57
58 static ParseResult parse(const mbgl::style::conversion::Convertible&, ParsingContext&);
59
60 EvaluationResult evaluate(const EvaluationContext& params) const override;
61 void eachChild(const std::function<void(const Expression&)>&) const override;
62
63 bool operator==(const Expression& e) const override {
64 if (e.getKind() == Kind::Var) {
65 auto rhs = static_cast<const Var*>(&e);
66 return *value == *(rhs->value);
67 }
68 return false;
69 }
70
71 std::vector<optional<Value>> possibleOutputs() const override;
72
73 mbgl::Value serialize() const override;
74 std::string getOperator() const override { return "var"; }
75
76 const std::shared_ptr<Expression>& getBoundExpression() const { return value; }
77
78private:
79 std::string name;
80 std::shared_ptr<Expression> value;
81};
82
83} // namespace expression
84} // namespace style
85} // namespace mbgl
86

source code of qtlocation/src/3rdparty/mapbox-gl-native/include/mbgl/style/expression/let.hpp