From 5008c26a604876bcad09c868aa2ec4a2c8b64e35 Mon Sep 17 00:00:00 2001 From: bjculkin Date: Fri, 31 Mar 2017 08:54:20 -0400 Subject: Move Pratt Parser to new project --- .../parserutils/pratt/commands/UnaryCommand.java | 47 ++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 JPratt/src/main/java/bjc/utils/parserutils/pratt/commands/UnaryCommand.java (limited to 'JPratt/src/main/java/bjc/utils/parserutils/pratt/commands/UnaryCommand.java') diff --git a/JPratt/src/main/java/bjc/utils/parserutils/pratt/commands/UnaryCommand.java b/JPratt/src/main/java/bjc/utils/parserutils/pratt/commands/UnaryCommand.java new file mode 100644 index 0000000..c608362 --- /dev/null +++ b/JPratt/src/main/java/bjc/utils/parserutils/pratt/commands/UnaryCommand.java @@ -0,0 +1,47 @@ +package bjc.utils.parserutils.pratt.commands; + +import bjc.utils.data.ITree; +import bjc.utils.data.Tree; +import bjc.utils.parserutils.ParserException; +import bjc.utils.parserutils.pratt.ParserContext; +import bjc.utils.parserutils.pratt.Token; + +/** + * A unary operator. + * + * @author bjculkin + * + * @param + * The key type of the tokens. + * + * @param + * The value type of the tokens. + * + * @param + * The state type of the parser. + */ +public class UnaryCommand extends AbstractInitialCommand { + private final int nullPwer; + + /** + * Create a new unary command. + * + * @param precedence + * The precedence of this operator. + */ + public UnaryCommand(int precedence) { + if(precedence < 0) { + throw new IllegalArgumentException("Precedence must be non-negative"); + } + + nullPwer = precedence; + } + + @Override + protected ITree> intNullDenotation(Token operator, ParserContext ctx) + throws ParserException { + ITree> opr = ctx.parse.parseExpression(nullPwer, ctx.tokens, ctx.state, false); + + return new Tree<>(operator, opr); + } +} \ No newline at end of file -- cgit v1.2.3