flex and bison

var/spack/packages/bison/package.py

+from spack import *
+
+class Bison(Package):
+    """Bison is a general-purpose parser generator that converts 
+    an annotated context-free grammar into a deterministic LR or 
+    generalized LR (GLR) parser employing LALR(1) parser tables."""
+
+    homepage = "http://www.gnu.org/software/bison/"
+    url      = "http://ftp.gnu.org/gnu/bison/bison-3.0.tar.gz"
+
+    version('3.0.4', 'a586e11cd4aff49c3ff6d3b6a4c9ccf8')
+
+    def install(self, spec, prefix):
+        configure("--prefix=%s" % prefix)
+
+        make()
+        make("install")

var/spack/packages/flex/package.py

+from spack import *
+
+class Flex(Package):
+    """Flex is a tool for generating scanners."""
+
+    homepage = "http://flex.sourceforge.net/"
+    url      = "http://download.sourceforge.net/flex/flex-2.5.39.tar.gz"
+
+    version('2.5.39', 'e133e9ead8ec0a58d81166b461244fde')
+
+    def install(self, spec, prefix):
+        configure("--prefix=%s" % prefix)
+
+        make()
+        make("install")