From f394306a4b65a3328551f9f6b8d4abff8bfd5b27 Mon Sep 17 00:00:00 2001 From: bjculkin Date: Wed, 12 Apr 2017 10:46:51 -0400 Subject: Package reorganization --- .../bjc/pratt/commands/impls/InitialCommands.java | 171 +++++++++++++++++++++ 1 file changed, 171 insertions(+) create mode 100644 JPratt/src/main/java/bjc/pratt/commands/impls/InitialCommands.java (limited to 'JPratt/src/main/java/bjc/pratt/commands/impls/InitialCommands.java') diff --git a/JPratt/src/main/java/bjc/pratt/commands/impls/InitialCommands.java b/JPratt/src/main/java/bjc/pratt/commands/impls/InitialCommands.java new file mode 100644 index 0000000..8da758a --- /dev/null +++ b/JPratt/src/main/java/bjc/pratt/commands/impls/InitialCommands.java @@ -0,0 +1,171 @@ +package bjc.pratt.commands.impls; + +import static bjc.pratt.blocks.ParseBlocks.repeating; +import static bjc.pratt.blocks.ParseBlocks.simple; +import static bjc.pratt.blocks.ParseBlocks.trigger; + +import java.util.function.UnaryOperator; + +import bjc.pratt.blocks.ParseBlock; +import bjc.pratt.commands.InitialCommand; +import bjc.pratt.tokens.Token; +import bjc.utils.data.ITree; + +/** + * * Contains factory methods for producing common implementations of + * {@link InitialCommand} + * + * @author EVE + * + */ +public class InitialCommands { + /** + * Create a new unary operator. + * + * @param precedence + * The precedence of the operator. + * + * @return A command implementing that operator. + */ + public static InitialCommand unary(final int precedence) { + return new UnaryCommand<>(precedence); + } + + /** + * Create a new grouping operator. + * + * @param precedence + * The precedence of the expression in the operator. + * + * @param term + * The type that closes the group. + * + * @param mark + * The token for the AST node of the group. + * + * @return A command implementing the operator. + */ + public static InitialCommand grouping(final int precedence, final K term, + final Token mark) { + final ParseBlock innerBlock = simple(precedence, term, null); + + return new GroupingCommand<>(innerBlock, mark); + } + + /** + * Create a new leaf operator. + * + * @return A command implementing the operator. + */ + public static InitialCommand leaf() { + return new LeafCommand<>(); + } + + /** + * Create a new pre-ternary operator, like an if-then-else statement. + * + * @param cond1 + * The priority of the first block. + * + * @param block1 + * The priority of the second block. + * + * @param block2 + * The priority of the third block. + * + * @param mark1 + * The marker that ends the first block. + * + * @param mark2 + * The marker that ends the second block. + * + * @param term + * The token for the AST node of the group. + * + * @return A command implementing the operator. + */ + public static InitialCommand preTernary(final int cond1, final int block1, final int block2, + final K mark1, final K mark2, final Token term) { + final ParseBlock condBlock = simple(cond1, mark1, null); + final ParseBlock opblock1 = simple(block1, mark2, null); + final ParseBlock opblock2 = simple(block2, null, null); + + return new PreTernaryCommand<>(condBlock, opblock1, opblock2, term); + } + + /** + * Create a new named constant. + * + * @param val + * The value of the constant. + * + * @return A command implementing the constant. + */ + public static InitialCommand constant(final ITree> val) { + return new ConstantCommand<>(val); + } + + /** + * Create a new delimited command. This is for block-like constructs. + * + * @param inner + * The precedence of the inner blocks. + * + * @param delim + * The marker between sub-blocks. + * + * @param mark + * The block terminator. + * + * @param term + * The token for the AST node of the group. + * + * @param onEnter + * The function to apply to the state on entering the + * block. + * + * @param onDelim + * The function to apply to the state on finishing a + * sub-block. + * + * @param onExit + * The function to apply to the state on exiting the + * block. + * + * @param statement + * Whether or not the sub-blocks are statements or + * expressions. + * + * @return A command implementing the operator. + */ + public static InitialCommand delimited(final int inner, final K delim, final K mark, + final Token term, final UnaryOperator onEnter, final UnaryOperator onDelim, + final UnaryOperator onExit, final boolean statement) { + final ParseBlock innerBlock = simple(inner, null, null); + final ParseBlock delimsBlock = repeating(innerBlock, delim, mark, term, onDelim); + final ParseBlock scopedBlock = trigger(delimsBlock, onEnter, onExit); + + final GroupingCommand command = new GroupingCommand<>(scopedBlock, term); + + /* + * Remove the wrapper layer from grouping-command on top of + * RepeatingParseBlock. + */ + return denest(command); + } + + /** + * Create a new denesting command. + * + * This removes one tree-level, and is useful when combining complex + * parse blocks with commands. + * + * @param comm + * The command to denest. + * + * @return A command that denests the result of the provided command. + */ + public static InitialCommand denest(final InitialCommand comm) { + return new DenestingCommand<>(comm); + } +} \ No newline at end of file -- cgit v1.2.3