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Diffstat (limited to 'BJC-Utils2/src/main/java/bjc/utils/parserutils/TreeConstructor.java')
-rw-r--r--BJC-Utils2/src/main/java/bjc/utils/parserutils/TreeConstructor.java125
1 files changed, 0 insertions, 125 deletions
diff --git a/BJC-Utils2/src/main/java/bjc/utils/parserutils/TreeConstructor.java b/BJC-Utils2/src/main/java/bjc/utils/parserutils/TreeConstructor.java
deleted file mode 100644
index 90141ef..0000000
--- a/BJC-Utils2/src/main/java/bjc/utils/parserutils/TreeConstructor.java
+++ /dev/null
@@ -1,125 +0,0 @@
-package bjc.utils.parserutils;
-
-import java.util.Deque;
-import java.util.LinkedList;
-import java.util.function.Function;
-import java.util.function.Predicate;
-
-import bjc.utils.data.IHolder;
-import bjc.utils.data.IPair;
-import bjc.utils.data.ITree;
-import bjc.utils.data.Identity;
-import bjc.utils.data.Pair;
-import bjc.utils.funcdata.IList;
-
-/**
- * Creates a parse tree from a postfix expression
- *
- * @author ben
- *
- */
-public class TreeConstructor {
- /**
- * Alias interface for special operator types.
- *
- * @param <TokenType>
- * The token type of the tree.
- */
- public interface QueueFlattener<TokenType> extends Function<Deque<ITree<TokenType>>, ITree<TokenType>> {
-
- }
-
- /*
- * Alias for constructor state.
- */
- static final class ConstructorState<TokenType> extends Pair<Deque<ITree<TokenType>>, ITree<TokenType>> {
- public ConstructorState(final Deque<ITree<TokenType>> left, final ITree<TokenType> right) {
- super(left, right);
- }
-
- public ConstructorState(final IPair<Deque<ITree<TokenType>>, ITree<TokenType>> par) {
- super(par.getLeft(), par.getRight());
- }
- }
-
- /**
- * Construct a tree from a list of tokens in postfix notation
- *
- * Only binary operators are accepted.
- *
- * @param <TokenType>
- * The elements of the parse tree
- * @param tokens
- * The list of tokens to build a tree from
- * @param isOperator
- * The predicate to use to determine if something is a
- * operator
- * @return A AST from the expression
- */
- public static <TokenType> ITree<TokenType> constructTree(final IList<TokenType> tokens,
- final Predicate<TokenType> isOperator) {
- /*
- * Construct a tree with no special operators
- */
- return constructTree(tokens, isOperator, op -> false, null);
- }
-
- /**
- * Construct a tree from a list of tokens in postfix notation.
- *
- * Only binary operators are accepted by default. Use the last two
- * parameters to handle non-binary operators.
- *
- * @param <TokenType>
- * The elements of the parse tree.
- *
- * @param tokens
- * The list of tokens to build a tree from.
- *
- * @param isOperator
- * The predicate to use to determine if something is a
- * operator.
- *
- * @param isSpecialOperator
- * The predicate to use to determine if an operator needs
- * special handling.
- *
- * @param handleSpecialOperator
- * The function to use to handle special case operators.
- *
- * @return A AST from the expression
- *
- */
- public static <TokenType> ITree<TokenType> constructTree(final IList<TokenType> tokens,
- final Predicate<TokenType> isOperator, final Predicate<TokenType> isSpecialOperator,
- final Function<TokenType, QueueFlattener<TokenType>> handleSpecialOperator) {
- /*
- * Make sure our parameters are valid
- */
- if (tokens == null)
- throw new NullPointerException("Tokens must not be null");
- else if (isOperator == null)
- throw new NullPointerException("Operator predicate must not be null");
- else if (isSpecialOperator == null)
- throw new NullPointerException("Special operator determiner must not be null");
-
- /*
- * Here is the state for the tree construction
- */
- final IHolder<ConstructorState<TokenType>> initialState = new Identity<>(
- new ConstructorState<>(new LinkedList<>(), null));
-
- /*
- * Transform each of the tokens
- */
- tokens.forEach(new TokenTransformer<>(initialState, isOperator, isSpecialOperator,
- handleSpecialOperator));
-
- /*
- * Grab the tree from the state
- */
- return initialState.unwrap(pair -> {
- return pair.getRight();
- });
- }
-}