27 lines
863 B
C#
27 lines
863 B
C#
using Convention.RScript.Parser;
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using System.Diagnostics.CodeAnalysis;
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namespace Convention.RScript.Runner
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{
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public class BackpointRunner : JumpRuntimePointerRunner
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{
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[return: MaybeNull]
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public override object Run(ExpressionParser parser, RScriptSentence sentence, RScriptContext context)
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{
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// 检查并跳转到上次跳转的位置
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if (parser.Evaluate<bool>(sentence.content))
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{
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if (context.GotoPointerStack.Count == 0)
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{
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throw new RScriptRuntimeException($"No position to back.", context.CurrentRuntimePointer);
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}
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else
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{
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DoJumpRuntimePointer(parser, context.GotoPointerStack.Pop(), context);
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}
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}
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return null;
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}
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}
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}
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