Check for error opening flexrule file. Cleaned example.

cstlempy.pyx

@@ -9,6 +9,7 @@ cdef extern from "tinylemmatizer.h":
 def init(Str):
     cdef int Err
     startProc(bytes(Str,'iso8859-1'),&Err)
+    return Err
 
 # Function to lemmatize a full form
 def lemmatize(Str):

launch.py

@@ -6,13 +6,22 @@
 import cstlempy
 
 filename = "flexrules"
-print("Initialise cstlempy with the call 'cstlempy.init("+filename+")'.\n")
-cstlempy.init(filename)
+print("Initialise cstlempy with the call 'cstlempy.init(\""+filename+"\")'.\n")
+Err = cstlempy.init(filename)
+
+if(Err == 0):
+    print("Initialization succeeded.\n")
+    cstlempyFullForm = "went"
+    print("Going to call lemmatize(<full form>).\n\nThe full form is this one: "+cstlempyFullForm)
+    answer = cstlempy.lemmatize(cstlempyFullForm)
+    print('Answer from cstlempy:      '+answer+'\n')
+elif(Err == 1):
+    print("Cannot open '" + filename + "'.\n")
+elif(Err ==2):
+    print("Something went wrong while reading '" + filename + "'.\n")
+else:
+    print("An unknown error occurred.\n")
 
-cstlempyFullForm = "went"
-print("Going to call lemmatize(<full form>).\n\nThe full form is this one: "+cstlempyFullForm)
-answer = cstlempy.lemmatize(cstlempyFullForm)
-print('Answer from cstlempy:      '+answer+'\n')
 cstlempy.final()
-print("We have called cstlempy.final(), so now cstlempy is not available until we call\n'cstlempy.init()' again.")
+print("We have called 'cstlempy.final()', so now cstlempy is not available until we call 'cstlempy.init()' again.")