Rudimentary CLI for new die implementation

1 files changed, 88 insertions, 0 deletions

diff --git a/dice/src/example/java/bjc/dicelang/neodice/commands/Command.java b/dice/src/example/java/bjc/dicelang/neodice/commands/Command.java
new file mode 100644
index 0000000..8460104
--- /dev/null
+++ b/dice/src/example/java/bjc/dicelang/neodice/commands/Command.java
@@ -0,0 +1,88 @@
+package bjc.dicelang.neodice.commands;
+
+import java.util.*;
+import java.util.function.*;
+
+import bjc.dicelang.neodice.*;
+import bjc.dicelang.neodice.statements.*;
+
+/**
+ * A single CLI command.
+ * 
+ * @author Ben Culkin
+ *
+ */
+@FunctionalInterface
+public interface Command {
+	/**
+	 * Execute this command.
+	 * 
+	 * @param words The remaining input.
+	 * @param state The current state.
+	 * 
+	 * @return The result of executing this command.
+	 */
+	public StatementValue execute(Iterator<String> words, DieBoxCLI state);
+	
+	/**
+	 * Get the 'short help' or usage summary for this command.
+	 * 
+	 * @return The short help for this command.
+	 */
+	default String shortHelp() {
+		return "no short help";
+	}
+	
+	/**
+	 * Get the 'long help' or detailed usage for this command.
+	 * 
+	 * @return The long help for this command.
+	 */
+	default String longHelp() {
+		return "no long help";
+	}
+	
+	/**
+	 * Create a new command, backed by a function.
+	 * 
+	 * @param executor The function which backs the command.
+	 * @param shortHelp The short help string.
+	 * @param longHelp The long help string.
+	 * 
+	 * @return A command backed by the function, with help.
+	 */
+	static Command newCommand(
+			BiFunction<Iterator<String>, DieBoxCLI, StatementValue> executor,
+			String shortHelp, String longHelp) {
+		return new FunctionalCommand(executor, shortHelp, longHelp);
+	}
+}
+
+class FunctionalCommand implements Command {
+	private final BiFunction<Iterator<String>, DieBoxCLI, StatementValue> executor;
+	private final String shortHelp;
+	private final String longHelp;
+	
+	public FunctionalCommand(
+			BiFunction<Iterator<String>, DieBoxCLI, StatementValue> executor, String shortHelp,
+			String longHelp) {
+		this.executor = executor;
+		this.shortHelp = shortHelp;
+		this.longHelp = longHelp;
+	}
+
+	@Override
+	public StatementValue execute(Iterator<String> words, DieBoxCLI state) {
+		return executor.apply(words, state);
+	}
+	
+	@Override
+	public String shortHelp() {
+		return shortHelp;
+	}
+	
+	@Override
+	public String longHelp() {
+		return longHelp;
+	}
+}
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