X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=blobdiff_plain;f=source%2Ffs%2Fpath.h;h=210b5d93d14c88bf136d07f25a5ddc78c7fc89e2;hp=ed9cc7985b62d863f86a6bc19726de692791d077;hb=6c958cd2d8806063580f836e4c3d486832af9635;hpb=e1452710edb6b1d0ebceb4b9273dae4b2f899630

diff --git a/source/fs/path.h b/source/fs/path.h
index ed9cc79..210b5d9 100644
--- a/source/fs/path.h
+++ b/source/fs/path.h
@@ -3,6 +3,7 @@
 
 #include <ostream>
 #include <string>
+#include <vector>
 
 namespace Msp {
 namespace FS {
@@ -20,64 +21,89 @@ enum
 Stores a filesystem path.  Paths are always stored in a normalized form; there
 are never any "." or ".." components in the middle of the path, and relative
 paths always begin with a single "." component or a sequence ".." components.
+As a special case, calling the constructor with no arguments or with an empty
+string will construct an empty path; this can be usedful as an invalid value.
+
+A path can also be treated as an array of components, supporting indexing,
+iteration and slicing.  In this context the root directory is treated as a
+component of its own.
 */
 class Path
 {
+private:
+	typedef std::vector<std::string::size_type> PositionArray;
+
 public:
 	class Iterator
 	{
-		friend class Path;
-
 	private:
-		const Path &path;
-		std::string::size_type start,end;
+		const Path *path;
+		PositionArray::const_iterator iter;
+		bool end;
 
-		Iterator(const Path &);
+		Iterator(const Path &, bool = false);
 	public:
+		static Iterator at_begin(const Path &p) { return Iterator(p); }
+		static Iterator at_end(const Path &p) { return Iterator(p, true); }
+
 		Iterator &operator++();
 		Iterator &operator--();
 		std::string operator*() const;
-		bool operator==(const Iterator &i) const { return (start==i.start && end==i.end); }
+		bool operator==(const Iterator &i) const { return (iter==i.iter && end==i.end); }
 		bool operator!=(const Iterator &i) const { return !(*this==i); }
 	};
 
 private:
 	std::string path;
+	std::vector<std::string::size_type> separators;
 
 public:
 	Path();
 	Path(const std::string &);
 	Path(const char *);
+private:
+	void init(const std::string &);
 
+public:
+	/// Returns the path as a string.
 	const std::string &str() const { return path; }
 
 	/// Returns the number of components in the path.
 	unsigned size() const;
 
+	/** Indicates whether the path is empty.  This really means empty; a path
+	pointing to the current directory is not empty. */
 	bool empty() const { return path.empty(); }
 
-	/// Determines whether the path starts from the root directory
+	/// Determines whether the path starts from the root directory.
 	bool is_absolute() const;
 
 	/// Extracts a range of components from the path.
 	Path subpath(unsigned start, unsigned count = static_cast<unsigned>(-1)) const;
 
-	/// Concatenates this path with another one, with usual filesystem semantics
+	/// Concatenates this path with another one, with usual filesystem semantics.
 	Path operator/(const Path &p) const;
 	Path &operator/=(const Path &);
 
-	/**
-	Extracts a single component from the path.  Negative indices count from the
-	end of the path.
-	*/
+private:
+	/** Adds a component to the path.  It must not contain the directory
+	separator character. */
+	void add_component(const std::string &);
+
+public:
+	/** Extracts a single component from the path.  Negative indices count from
+	the end of the path. */
 	std::string operator[](int) const;
 
 	bool operator==(const Path &) const;
-	Iterator begin() const;
-	Iterator end() const;
-private:
-	void init(const std::string &);
-	void add_component(const std::string &);
+	bool operator<(const Path &) const;
+	bool operator>(const Path &) const;
+	bool operator<=(const Path &other) const { return !(*this>other); }
+	bool operator>=(const Path &other) const { return !(*this<other); }
+	bool operator!=(const Path &other) const { return !(*this==other); }
+
+	Iterator begin() const { return Iterator::at_begin(*this); }
+	Iterator end() const { return Iterator::at_end(*this); }
 };
 
 inline std::ostream &operator<<(std::ostream &o, const Path &p) { o<<p.str(); return o; }