From c82452e59b1547392c3e89d08d9173cc6dc79e23 Mon Sep 17 00:00:00 2001 From: bjculkin Date: Wed, 5 Apr 2017 15:35:13 -0400 Subject: Reorganize --- .../java/bjc/pratt/commands/TernaryCommand.java | 77 ++++++++++++++++++++++ 1 file changed, 77 insertions(+) create mode 100644 JPratt/src/main/java/bjc/pratt/commands/TernaryCommand.java (limited to 'JPratt/src/main/java/bjc/pratt/commands/TernaryCommand.java') diff --git a/JPratt/src/main/java/bjc/pratt/commands/TernaryCommand.java b/JPratt/src/main/java/bjc/pratt/commands/TernaryCommand.java new file mode 100644 index 0000000..bac12cd --- /dev/null +++ b/JPratt/src/main/java/bjc/pratt/commands/TernaryCommand.java @@ -0,0 +1,77 @@ +package bjc.pratt.commands; + +import bjc.pratt.ParseBlock; +import bjc.pratt.ParserContext; +import bjc.pratt.Token; +import bjc.utils.data.ITree; +import bjc.utils.data.Tree; +import bjc.utils.parserutils.ParserException; + +/** + * A ternary command, like C's ?: + * + * @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 TernaryCommand extends BinaryPostCommand { + private ParseBlock innerBlck; + + private Token mark; + + private boolean nonassoc; + + /** + * Create a new ternary command. + * + * @param precedence + * The precedence of this operator. + * + * @param innerBlock + * The representation of the inner block of the + * expression. + * + * @param marker + * The token to use as the root of the AST node. + * + * @param isNonassoc + * Whether or not the conditional is associative. + */ + public TernaryCommand(int precedence, ParseBlock innerBlock, Token marker, boolean isNonassoc) { + super(precedence); + + if (innerBlock == null) + throw new NullPointerException("Inner block must not be null"); + else if (marker == null) throw new NullPointerException("Marker must not be null"); + + innerBlck = innerBlock; + mark = marker; + nonassoc = isNonassoc; + } + + @Override + public ITree> denote(ITree> operand, Token operator, ParserContext ctx) + throws ParserException { + ITree> inner = innerBlck.parse(ctx); + + ITree> outer = ctx.parse.parseExpression(1 + leftBinding(), ctx.tokens, ctx.state, false); + + return new Tree<>(mark, inner, operand, outer); + } + + @Override + public int nextBinding() { + if (nonassoc) { + return leftBinding() - 1; + } else { + return leftBinding(); + } + } +} \ No newline at end of file -- cgit v1.2.3