1 files changed, 45 insertions, 0 deletions
diff --git a/tests/lex_hedit.py b/tests/lex_hedit.py
new file mode 100644
index 0000000..9f724d0
--- /dev/null
+++ b/tests/lex_hedit.py
@@ -0,0 +1,45 @@
+# -----------------------------------------------------------------------------
+# hedit.py
+#
+# Paring of Fortran H Edit descriptions (Contributed by Pearu Peterson)
+#
+# These tokens can't be easily tokenized because they are of the following
+# form:
+#
+#   nHc1...cn
+#
+# where n is a positive integer and c1 ... cn are characters.
+#
+# This example shows how to modify the state of the lexer to parse
+# such tokens
+# -----------------------------------------------------------------------------
+
+import ply.lex as lex
+
+tokens = (
+    'H_EDIT_DESCRIPTOR',
+    )
+
+# Tokens
+t_ignore = " \t\n"
+
+def t_H_EDIT_DESCRIPTOR(t):
+    r"\d+H.*"                     # This grabs all of the remaining text
+    i = t.value.index('H')
+    n = eval(t.value[:i])
+    
+    # Adjust the tokenizing position
+    t.lexer.lexpos -= len(t.value) - (i+1+n)
+    t.value = t.value[i+1:i+1+n]
+    return t                                  
+    
+def t_error(t):
+    print("Illegal character '%s'" % t.value[0])
+    t.lexer.skip(1)
+    
+# Build the lexer
+lex.lex()
+lex.runmain(data="3Habc 10Habcdefghij 2Hxy")
+
+
+