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/blocks/SimpleParseBlock.java | 101 +++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 JPratt/src/main/java/bjc/pratt/blocks/SimpleParseBlock.java (limited to 'JPratt/src/main/java/bjc/pratt/blocks/SimpleParseBlock.java') diff --git a/JPratt/src/main/java/bjc/pratt/blocks/SimpleParseBlock.java b/JPratt/src/main/java/bjc/pratt/blocks/SimpleParseBlock.java new file mode 100644 index 0000000..acddd3b --- /dev/null +++ b/JPratt/src/main/java/bjc/pratt/blocks/SimpleParseBlock.java @@ -0,0 +1,101 @@ +package bjc.pratt.blocks; + +import java.util.function.Predicate; + +import bjc.pratt.ParseBlock; +import bjc.pratt.ParserContext; +import bjc.pratt.Token; +import bjc.utils.data.ITree; +import bjc.utils.parserutils.ParserException; + +/** + * Simple implementation of {@link ParseBlock} + * + * @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 SimpleParseBlock implements ParseBlock { + private int pow; + + private K term; + + private Predicate>> validatr; + + /** + * Create a new block. + * + * @param precedence + * The precedence of this block. + * + * @param terminator + * The token type that terminates the block. If this is + * null, don't check for a terminator. + * + * @param validator + * The predicate to apply to blocks. + */ + public SimpleParseBlock(int precedence, K terminator, Predicate>> validator) { + if (precedence < 0) throw new IllegalArgumentException("Precedence must be non-negative"); + + pow = precedence; + term = terminator; + validatr = validator; + } + + @Override + public ITree> parse(ParserContext ctx) throws ParserException { + ITree> res = ctx.parse.parseExpression(pow, ctx.tokens, ctx.state, false); + + if (term != null) { + ctx.tokens.expect(term); + } + + if (validatr == null || validatr.test(res)) { + return res; + } + + throw new ParserException("Block failed validation"); + } + + @Override + public int hashCode() { + final int prime = 31; + + int result = 1; + + result = prime * result + pow; + result = prime * result + ((term == null) ? 0 : term.hashCode()); + + return result; + } + + @Override + public boolean equals(Object obj) { + if (this == obj) return true; + if (obj == null) return false; + if (!(obj instanceof SimpleParseBlock)) return false; + + SimpleParseBlock other = (SimpleParseBlock) obj; + + if (pow != other.pow) return false; + + if (term == null) { + if (other.term != null) return false; + } else if (!term.equals(other.term)) return false; + + return true; + } + + @Override + public String toString() { + return String.format("ParseBlock [pow=%s, term='%s']", pow, term); + } +} \ No newline at end of file -- cgit v1.2.3