我是 Irony 编程的新手。我正在处理的第一个测试示例是计算数学形状(面积、体积......)
在简单模式下,它工作正常。但挑战是我想让它成为可选的。例如,如果我选择圆形作为形状,那么我只需要半径。另外,如果我选择矩形作为形状,我需要高度和宽度。所以,我想知道当形状是圆形时如何获得一个数字作为半径,以及当形状是矩形时如何获得 2 或 3 个数字。
var program = new NonTerminal("program");
var shapeType = new NonTerminal("shapeType");
var shapeTypes = new NonTerminal("shapeTypes");
var circle = new NonTerminal("circle");
var square = new NonTerminal("square");
var rectangle = new NonTerminal("rectangle");
var triangle = new NonTerminal("triangle");
var commandList = new NonTerminal("commandList");
var command = new NonTerminal("command");
var width = new NonTerminal("width");
var height = new NonTerminal("height");
var length = new NonTerminal("length");
var radius = new NonTerminal("radius");
var number = new NumberLiteral("number");
var operation = new NonTerminal("operation");
this.Root = program;
program.Rule = shapeType + radius + commandList |
shapeType + length + commandList |
shapeType + width + commandList |
shapeType + length + width + commandList |
shapeType + height + commandList |
shapeType + length + width + height + commandList;
shapeType.Rule = Symbol("set") + "shape" + ":" + shapeTypes + ".";
shapeTypes.Rule = Symbol("circle") | "square" | "rectangle" | "triangle";
radius.Rule = Symbol("set") + "radius" + ":" + number + ".";
height.Rule = Symbol("set") + "height" + ":" + number + ".";
width.Rule = Symbol("set") + "width" + ":" + number + ".";
length.Rule = Symbol("set") + "length" + ":" + number + ".";
triangle.Rule = height + width | height + width + length;
rectangle.Rule = height + width | height + width + length;
square.Rule = height + width | height + width + length;
circle.Rule = radius;
operation.Rule = Symbol("area") | "volume";
commandList.Rule = MakeStarRule(commandList, null, command);
command.Rule = Symbol("what") + "is" + operation + ".";
它的行为是这样的:对于圆形示例,我希望我的代码只接收半径而不是更多(如下面的代码 - 清单 1)。但是,当语法像清单 2 时,它也可以工作。所以,我想要编译中的特定情况。
清单 1
set shape : circle.
set radius : 10.
what is area.
清单 2
set shape : circle.
set length : 10.
set width : 5.
what is area.
它们都得出相同的答案,我们知道清单 2 的参数是错误的。