public static boolean isIndex(String key) {
		return key == null ? false : key.startsWith("[") && key.endsWith("]");
	}
Check if the given key is a bracketed index

@param key the key to check
@return true if it is an index
Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/model/target/path/KeyPath.java