diff options
Diffstat (limited to 'BJC-Utils2/src/main/java/bjc/utils/funcdata')
3 files changed, 68 insertions, 2 deletions
diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcdata/ITree.java b/BJC-Utils2/src/main/java/bjc/utils/funcdata/ITree.java index 624c9d6..7f28682 100644 --- a/BJC-Utils2/src/main/java/bjc/utils/funcdata/ITree.java +++ b/BJC-Utils2/src/main/java/bjc/utils/funcdata/ITree.java @@ -114,8 +114,8 @@ public interface ITree<ContainedType> { * The function to use to transform tokens * @return A tree with the token types transformed */ - public <MappedType> ITree<MappedType> transformTree( - Function<ContainedType, MappedType> transformer); + public <MappedType> ITree<MappedType> + transformTree(Function<ContainedType, MappedType> transformer); /** * Perform an action on each part of the tree @@ -142,4 +142,17 @@ public interface ITree<ContainedType> { public <MappedType> ITree<MappedType> rebuildTree( Function<ContainedType, MappedType> leafTransformer, Function<ContainedType, MappedType> operatorTransformer); + + /** + * Do a top-down transform of the tree + * + * @param transformPicker + * The function to use to pick how to progress + * @param transformer + * The function used to transform picked subtrees + * @return The tree with the transform applied to picked subtrees + */ + public ITree<ContainedType> topDownTransform( + Function<ContainedType, TopDownTransformResult> transformPicker, + UnaryOperator<ITree<ContainedType>> transformer); } diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcdata/TopDownTransformResult.java b/BJC-Utils2/src/main/java/bjc/utils/funcdata/TopDownTransformResult.java new file mode 100644 index 0000000..9aec2b9 --- /dev/null +++ b/BJC-Utils2/src/main/java/bjc/utils/funcdata/TopDownTransformResult.java @@ -0,0 +1,22 @@ +package bjc.utils.funcdata; + +/** + * Represents the results for doing a top-down transform of a tree + * + * @author ben + * + */ +public enum TopDownTransformResult { + /** + * Do not do anything to this node, and ignore it's children + */ + SKIP, + /** + * Transform this node, and don't touch its children + */ + TRANSFORM, + /** + * Ignore this node, and traverse its children + */ + PASSTHROUGH; +} diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcdata/Tree.java b/BJC-Utils2/src/main/java/bjc/utils/funcdata/Tree.java index 5ee4200..03a1f93 100644 --- a/BJC-Utils2/src/main/java/bjc/utils/funcdata/Tree.java +++ b/BJC-Utils2/src/main/java/bjc/utils/funcdata/Tree.java @@ -262,4 +262,35 @@ public class Tree<ContainedType> implements ITree<ContainedType> { }); } } + + @Override + public ITree<ContainedType> topDownTransform( + Function<ContainedType, TopDownTransformResult> transformPicker, + UnaryOperator<ITree<ContainedType>> transformer) { + TopDownTransformResult transformResult = + transformPicker.apply(data); + + switch (transformResult) { + case PASSTHROUGH: + ITree<ContainedType> result = new Tree<>(data); + + if (hasChildren) { + children.forEach((child) -> { + result.addChild(child.topDownTransform( + transformPicker, transformer)); + }); + } + + return result; + case SKIP: + return this; + case TRANSFORM: + return transformer.apply(this); + default: + throw new IllegalArgumentException( + "Recieved unknown transform result " + + transformResult); + + } + } } |