Merge pull request #345 from VeriFIT/revert_opening_files

Revert "Rewrite opening files to fix compilation errors" #patch

bindings/python/libmata/parser.pxd

@@ -13,7 +13,6 @@ cdef extern from "<fstream>" namespace "std":
     cdef cppclass ifstream(istream):
         ifstream() except+
         ifstream(const char*) except +
-        void open(const char*)
 
 cdef extern from "mata/parser/re2parser.hh" namespace "mata::parser":
     cdef void create_nfa(CNfa*, string) except +

bindings/python/libmata/parser.pyx

@@ -44,7 +44,7 @@ def from_mata(src, alph.Alphabet alphabet):
 
     # either load single automata
     if isinstance(src, str):
-        fs.open(src.encode('utf-8'))
+        fs = parser.ifstream(src.encode('utf-8'))
         res_inter_aut = parser.parse_from_mf(parser.parse_mf(fs, True))
         result = mata_nfa.Nfa()
         if res_inter_aut[0].is_bitvector():
@@ -64,9 +64,9 @@ def from_mata(src, alph.Alphabet alphabet):
     else:
         automata = []
         for file in src:
-            fs.open(file.encode('utf-8'))
+            fs = parser.ifstream(file.encode('utf-8'))
             res_inter_aut = parser.parse_from_mf(parser.parse_mf(fs, True))
-            inter_aut.push_back(res_inter_aut[0])
+            inter_aut.emplace_back(res_inter_aut[0])
         if inter_aut[0].is_bitvector():
             mintermized_inter_aut = mintermization.c_mintermize_vec(inter_aut)
         else: