Support $^ escape sequence for newlines.

doc/manual.asciidoc

@@ -917,7 +917,13 @@ paths, where a space would otherwise separate filenames.  See below.)
 `$:` :: a colon.  (This is only necessary in `build` lines, where a colon
 would otherwise terminate the list of outputs.)
 
-`$^` :: a newline. Inserts '\n' ('\r\n' on Windows) into the resulting string.
+`$^` :: a newline _(available since Ninja 1.14)_.
+
+Inserts '\n' ('\r\n' on Windows) into the resulting string. This is useful to
+write build commands that require several shell lines as a single `command`
+value in the build plan.
+
+Requires `ninja_required_version` to be specified in the build file.
 
 `$$`:: a literal `$`.
 

src/manifest_parser.cc

@@ -68,7 +68,7 @@ bool ManifestParser::Parse(const string& filename, const string& input,
       // Check ninja_required_version immediately so we can exit
       // before encountering any syntactic surprises.
       if (name == "ninja_required_version")
-        CheckNinjaVersion(value, lexer_.manifest_version_major, lexer_.manifest_version_minor);
+        CheckNinjaVersion(value, &lexer_.manifest_version_major, &lexer_.manifest_version_minor);
       env_->AddBinding(name, value);
       break;
     }

src/version.cc

@@ -33,20 +33,20 @@ void ParseVersion(const string& version, int* major, int* minor) {
   }
 }
 
-void CheckNinjaVersion(const string& version, int &file_major, int &file_minor) {
+void CheckNinjaVersion(const string& version, int *file_major, int *file_minor) {
   int bin_major, bin_minor;
   ParseVersion(kNinjaVersion, &bin_major, &bin_minor);
-  ParseVersion(version, &file_major, &file_minor);
+  ParseVersion(version, file_major, file_minor);
 
-  if (bin_major > file_major) {
+  if (bin_major > *file_major) {
     Warning("ninja executable version (%s) greater than build file "
             "ninja_required_version (%s); versions may be incompatible.",
             kNinjaVersion, version.c_str());
     return;
   }
 
-  if ((bin_major == file_major && bin_minor < file_minor) ||
-      bin_major < file_major) {
+  if ((bin_major == *file_major && bin_minor < *file_minor) ||
+      bin_major < *file_major) {
     Fatal("ninja version (%s) incompatible with build file "
           "ninja_required_version version (%s).",
           kNinjaVersion, version.c_str());

src/version.h

@@ -26,7 +26,7 @@ void ParseVersion(const std::string& version, int* major, int* minor);
 
 /// Check whether \a version is compatible with the current Ninja version,
 /// aborting if not.
-void CheckNinjaVersion(const std::string& required_version, int &file_major,
-    int &file_minor);
+void CheckNinjaVersion(const std::string& required_version, int *file_major,
+    int *file_minor);
 
 #endif  // NINJA_VERSION_H_