diff --git a/parse b/parse
deleted file mode 100755
index 1dc61d2..0000000
Binary files a/parse and /dev/null differ
diff --git a/parse.c b/parse.c
index a9408b4..042bbba 100644
--- a/parse.c
+++ b/parse.c
@@ -3,7 +3,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#define YYRULECOUNT 11
+#define YYRULECOUNT 15
 #line 1 "parse.leg"
 
 
@@ -12,10 +12,17 @@
 #include <stdlib.h>
 #include "inputBuffer.c"
 ;
-enum op { String, Query, Star, Plus, Or, And, Class, Dot, Exc } ;
+enum op { String, Query, Star, Plus, Or, And, Class, Dot, Exc, Id } ;
 
 
 typedef union Node Node;
+typedef struct Symbol Symbol;
+typedef struct Array Array;
+typedef struct SymbolTable SymbolTable;
+struct Array {
+    Node **elements;
+    int length;
+};
 
 struct String  { enum op type;  char *string; int len; };
 struct Query   { enum op type;  Node *children[1]; };
@@ -24,8 +31,9 @@ struct Plus    { enum op type;  Node *children[1]; };
 struct Or      { enum op type;  Node *children[2]; };
 struct And     { enum op type;  Node *children[2]; };
 struct Class   { enum op type;  char *stringValue; int len; };
-struct Dot     { enum op type;};
+struct Dot     { enum op type; };
 struct Exc     { enum op type;  Node *children[1]; };
+struct Id      { enum op type; Symbol *symbol; };
 
 union Node {
     enum op type;
@@ -38,8 +46,30 @@ union Node {
     struct Class Class;
     struct Dot Dot;
     struct Exc Exc;
+    struct Id Id;
+};
+
+struct Symbol{
+  char* name;
+  Node *rule;
+};
+
+struct SymbolTable {
+    Symbol **elements;
+    int length;
 };
 
+#define SymbolTable_initialiser {0,0}
+SymbolTable symbolTable= SymbolTable_initialiser;
+
+Symbol *createSymbol(char *name) {
+    Symbol *symbol= calloc(1, sizeof(Symbol));
+    symbol->name= strdup(name);
+    return symbol;
+}
+
+
+
 
 #define new(type)			mkNode(sizeof(struct type),type)
 
@@ -58,6 +88,15 @@ Node *mkString(char *s)
     return node;
 }
 
+Node *mkId(char *s){
+  
+    Node *node= new(Id);
+    node->Id.symbol=createSymbol(s);
+    return node;
+}
+
+
+
 Node *mkQuery(Node *n)
 {
     Node *node= new(Query);
@@ -116,6 +155,16 @@ Node *mkExc(Node *n)
     return node;
 }
 
+Node *_checktype(Node *object, enum op type)
+{
+    if (object->type == type) return object;
+    fprintf(stderr, "\naccesing type %i as if it were a %i\n", object->type, type);
+    exit(1);
+    return 0;
+}
+
+#define get(object, type, member)	(_checktype(object, type)->type.member)
+
 void print(Node *node)
 {
     switch (node->type) {
@@ -154,6 +203,9 @@ void print(Node *node)
         printf("!");
         print(node->Exc.children[0]);
         return;   
+      case Id:
+        printf("%s\n",get(node,Id,symbol)->name);
+        return;
     }
     abort();
 }
@@ -175,6 +227,102 @@ else { \
     result=1; \
 }} 
 
+
+
+void move(SymbolTable *symbolTable, int a) {
+    symbolTable->length++;
+    symbolTable->elements= realloc(symbolTable->elements,sizeof(Node*) * symbolTable->length);
+    printf("begin\n");
+    for (int i= symbolTable->length-1; i >a; i--) {
+        symbolTable->elements[i] = symbolTable->elements[i-1];
+        printf("\n");
+        for(int i= 0; i<symbolTable->length; i++) {
+            printf("number : %i, name : %s, value : a\n",i, symbolTable->elements[i]->name);
+        }
+    }
+    printf("end\n");
+}
+
+void addSymbolSorted(SymbolTable *symbolTable, Symbol *symbol) {
+    int a=0;
+    int b= symbolTable->length-1;
+    int c;
+    //1 <b-a => no infinite loop with a and c = 0 et b =1
+    while (1 < b - a ) {
+        c= (a+b)/2;
+        if (strcmp(symbolTable->elements[c]->name, symbol->name) < 0) {
+            a= c;
+        } else {
+            b= c;
+        }
+    }
+    //b>-1 <=> symboleTable->length > 0
+    // this if is here to know if we put the symbol before or after a
+    if (b>-1 && strcmp(symbolTable->elements[a]->name, symbol->name) < 0) {
+        a++;
+    }
+    //we move all the symbols after a
+    move(symbolTable, a);
+    //we put the symbol at the right place
+    symbolTable->elements[a]->name = symbol->name;
+}
+
+int findSymbol(SymbolTable *symbolTable, char *name) {
+    for (int i= 0; i < symbolTable->length;i++) {
+        if (strcmp(symbolTable->elements[i]->name, name) == 0) {
+            return 1;
+        }
+    }
+    Symbol *symbol = createSymbol(name);
+    addSymbolSorted(symbolTable, symbol);
+    return 0;
+}
+
+Node *findSymbolSorted(SymbolTable *symbolTable, char *name) {
+    int a=0;
+    int b= symbolTable->length-1;
+    int c;
+    //1 <b-a => no infinite loop with a and c = 0 et b =1
+    while (1 < b - a ) {
+        c= (a+b)/2;
+        if (strcmp(symbolTable->elements[c]->name, name) < 0) {
+            a= c;
+        } else {
+            if (strcmp(symbolTable->elements[c]->name, name) > 0) {
+                b= c;
+            } else {
+                return symbolTable->elements[c]->rule;
+            }
+        }
+    }
+    //b>-1 <=> symboleTable->length > 0
+    // this if is here to know if we put the symbol before or after a
+    if (b>-1 && strcmp(symbolTable->elements[a]->name, name) < 0) {
+        a++;
+    }
+    //we move all the symbols after a
+    move(symbolTable, a);
+    //we put the symbol at the right place
+    symbolTable->elements[a]= createSymbol(name);
+    return 0;
+}
+
+void setRule(SymbolTable *symbolTable, char *name, Node *rule) {
+    for (int i= 0; i < symbolTable->length;i++) {
+        if (strcmp(symbolTable->elements[i]->name, name) == 0) {
+            symbolTable->elements[i]->rule= rule;
+            break;
+        }
+    }
+}
+
+void arrayAppend(Array *array, Node *statement) {
+    array->length++;
+    array->elements= realloc(array->elements,sizeof(Node*) * array->length);
+    array->elements[array->length-1] = statement;
+    }
+
+
 #define YYSTYPE Node *
 YYSTYPE yylval = 0;
 
@@ -447,16 +595,20 @@ YY_LOCAL(void) yySet(yycontext *yy, char *text, int count)   { yy->__val[count]=
 
 #define	YYACCEPT	yyAccept(yy, yythunkpos0)
 
-YY_RULE(int) yy_space(yycontext *yy); /* 11 */
-YY_RULE(int) yy_dot(yycontext *yy); /* 10 */
-YY_RULE(int) yy_class(yycontext *yy); /* 9 */
-YY_RULE(int) yy_string(yycontext *yy); /* 8 */
-YY_RULE(int) yy_atom(yycontext *yy); /* 7 */
-YY_RULE(int) yy_postfix(yycontext *yy); /* 6 */
-YY_RULE(int) yy_prefix(yycontext *yy); /* 5 */
-YY_RULE(int) yy_and(yycontext *yy); /* 4 */
-YY_RULE(int) yy_or(yycontext *yy); /* 3 */
-YY_RULE(int) yy__(yycontext *yy); /* 2 */
+YY_RULE(int) yy_space(yycontext *yy); /* 15 */
+YY_RULE(int) yy_rule(yycontext *yy); /* 14 */
+YY_RULE(int) yy_dot(yycontext *yy); /* 13 */
+YY_RULE(int) yy_class(yycontext *yy); /* 12 */
+YY_RULE(int) yy_string(yycontext *yy); /* 11 */
+YY_RULE(int) yy_atom(yycontext *yy); /* 10 */
+YY_RULE(int) yy_postfix(yycontext *yy); /* 9 */
+YY_RULE(int) yy_prefix(yycontext *yy); /* 8 */
+YY_RULE(int) yy_and(yycontext *yy); /* 7 */
+YY_RULE(int) yy_or(yycontext *yy); /* 6 */
+YY_RULE(int) yy_expression(yycontext *yy); /* 5 */
+YY_RULE(int) yy__(yycontext *yy); /* 4 */
+YY_RULE(int) yy_id(yycontext *yy); /* 3 */
+YY_RULE(int) yy_declaration(yycontext *yy); /* 2 */
 YY_RULE(int) yy_start(yycontext *yy); /* 1 */
 
 YY_ACTION(void) yy_1_dot(yycontext *yy, char *yytext, int yyleng)
@@ -466,7 +618,7 @@ YY_ACTION(void) yy_1_dot(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_1_dot\n"));
   {
-#line 198
+#line 352
   __=mkDot();
   }
 #undef yythunkpos
@@ -480,7 +632,7 @@ YY_ACTION(void) yy_1_class(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_1_class\n"));
   {
-#line 196
+#line 350
    __=mkClass(yytext) ;
   }
 #undef yythunkpos
@@ -494,13 +646,43 @@ YY_ACTION(void) yy_1_string(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_1_string\n"));
   {
-#line 194
+#line 348
    __ = mkString(yytext) ;
   }
 #undef yythunkpos
 #undef yypos
 #undef yy
 }
+YY_ACTION(void) yy_1_id(yycontext *yy, char *yytext, int yyleng)
+{
+#define __ yy->__
+#define yypos yy->__pos
+#define yythunkpos yy->__thunkpos
+  yyprintf((stderr, "do yy_1_id\n"));
+  {
+#line 346
+   __ = mkId(yytext) ;
+  }
+#undef yythunkpos
+#undef yypos
+#undef yy
+}
+YY_ACTION(void) yy_1_rule(yycontext *yy, char *yytext, int yyleng)
+{
+#define i yy->__val[-1]
+#define __ yy->__
+#define yypos yy->__pos
+#define yythunkpos yy->__thunkpos
+  yyprintf((stderr, "do yy_1_rule\n"));
+  {
+#line 344
+   __ = mkId(yytext) ;
+  }
+#undef yythunkpos
+#undef yypos
+#undef yy
+#undef i
+}
 YY_ACTION(void) yy_4_postfix(yycontext *yy, char *yytext, int yyleng)
 {
 #define s yy->__val[-1]
@@ -509,7 +691,7 @@ YY_ACTION(void) yy_4_postfix(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_4_postfix\n"));
   {
-#line 190
+#line 340
    __ = s;
   }
 #undef yythunkpos
@@ -525,7 +707,7 @@ YY_ACTION(void) yy_3_postfix(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_3_postfix\n"));
   {
-#line 189
+#line 339
    s = mkPlus(s) ;
   }
 #undef yythunkpos
@@ -541,7 +723,7 @@ YY_ACTION(void) yy_2_postfix(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_2_postfix\n"));
   {
-#line 188
+#line 338
    s = mkStar(s) ;
   }
 #undef yythunkpos
@@ -557,7 +739,7 @@ YY_ACTION(void) yy_1_postfix(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_1_postfix\n"));
   {
-#line 187
+#line 337
    s = mkQuery(s) ;
   }
 #undef yythunkpos
@@ -573,7 +755,7 @@ YY_ACTION(void) yy_2_prefix(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_2_prefix\n"));
   {
-#line 185
+#line 335
   __ = p;
   }
 #undef yythunkpos
@@ -589,7 +771,7 @@ YY_ACTION(void) yy_1_prefix(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_1_prefix\n"));
   {
-#line 184
+#line 334
   __ = mkExc(p);
   }
 #undef yythunkpos
@@ -606,7 +788,7 @@ YY_ACTION(void) yy_2_and(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_2_and\n"));
   {
-#line 182
+#line 332
    __ = p ;
   }
 #undef yythunkpos
@@ -624,7 +806,7 @@ YY_ACTION(void) yy_1_and(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_1_and\n"));
   {
-#line 181
+#line 331
    __ = mkAnd(p, a); ;
   }
 #undef yythunkpos
@@ -642,7 +824,7 @@ YY_ACTION(void) yy_2_or(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_2_or\n"));
   {
-#line 179
+#line 329
    __ = a ;
   }
 #undef yythunkpos
@@ -660,7 +842,7 @@ YY_ACTION(void) yy_1_or(yycontext *yy, char *yytext, int yyleng)
 #define yythunkpos yy->__thunkpos
   yyprintf((stderr, "do yy_1_or\n"));
   {
-#line 178
+#line 328
   __ = mkOr(o, a) ;
   }
 #undef yythunkpos
@@ -669,21 +851,23 @@ YY_ACTION(void) yy_1_or(yycontext *yy, char *yytext, int yyleng)
 #undef o
 #undef a
 }
-YY_ACTION(void) yy_1_start(yycontext *yy, char *yytext, int yyleng)
+YY_ACTION(void) yy_1_declaration(yycontext *yy, char *yytext, int yyleng)
 {
-#define o yy->__val[-1]
+#define e yy->__val[-1]
+#define i yy->__val[-2]
 #define __ yy->__
 #define yypos yy->__pos
 #define yythunkpos yy->__thunkpos
-  yyprintf((stderr, "do yy_1_start\n"));
+  yyprintf((stderr, "do yy_1_declaration\n"));
   {
-#line 176
-   yylval = o ;
+#line 326
+   setRule(&symbolTable,get(i, Id, symbol)->name, e) ;
   }
 #undef yythunkpos
 #undef yypos
 #undef yy
-#undef o
+#undef e
+#undef i
 }
 
 YY_RULE(int) yy_space(yycontext *yy)
@@ -708,155 +892,206 @@ YY_RULE(int) yy_space(yycontext *yy)
   yyprintf((stderr, "  fail %s @ %s\n", "space", yy->__buf+yy->__pos));
   return 0;
 }
+YY_RULE(int) yy_rule(yycontext *yy)
+{  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;  yyDo(yy, yyPush, 1, 0);
+  yyprintf((stderr, "%s\n", "rule"));  if (!yy_id(yy)) goto l9;  yyDo(yy, yySet, -1, 0);
+  {  int yypos10= yy->__pos, yythunkpos10= yy->__thunkpos;  if (!yymatchChar(yy, '=')) goto l10;  goto l9;
+  l10:;	  yy->__pos= yypos10; yy->__thunkpos= yythunkpos10;
+  }  yyDo(yy, yy_1_rule, yy->__begin, yy->__end);
+  yyprintf((stderr, "  ok   %s @ %s\n", "rule", yy->__buf+yy->__pos));  yyDo(yy, yyPop, 1, 0);
+  return 1;
+  l9:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  yyprintf((stderr, "  fail %s @ %s\n", "rule", yy->__buf+yy->__pos));
+  return 0;
+}
 YY_RULE(int) yy_dot(yycontext *yy)
 {  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;
-  yyprintf((stderr, "%s\n", "dot"));  if (!yy__(yy)) goto l9;  if (!yymatchChar(yy, '.')) goto l9;  if (!yy__(yy)) goto l9;  yyDo(yy, yy_1_dot, yy->__begin, yy->__end);  if (!yy__(yy)) goto l9;
+  yyprintf((stderr, "%s\n", "dot"));  if (!yy__(yy)) goto l11;  if (!yymatchChar(yy, '.')) goto l11;  if (!yy__(yy)) goto l11;  yyDo(yy, yy_1_dot, yy->__begin, yy->__end);  if (!yy__(yy)) goto l11;
   yyprintf((stderr, "  ok   %s @ %s\n", "dot", yy->__buf+yy->__pos));
   return 1;
-  l9:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  l11:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
   yyprintf((stderr, "  fail %s @ %s\n", "dot", yy->__buf+yy->__pos));
   return 0;
 }
 YY_RULE(int) yy_class(yycontext *yy)
 {  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;
-  yyprintf((stderr, "%s\n", "class"));  if (!yymatchChar(yy, '[')) goto l10;  if (!yy__(yy)) goto l10;  yyText(yy, yy->__begin, yy->__end);  {
+  yyprintf((stderr, "%s\n", "class"));  if (!yymatchChar(yy, '[')) goto l12;  if (!yy__(yy)) goto l12;  yyText(yy, yy->__begin, yy->__end);  {
 #define yytext yy->__text
 #define yyleng yy->__textlen
-if (!(YY_BEGIN)) goto l10;
+if (!(YY_BEGIN)) goto l12;
 #undef yytext
 #undef yyleng
   }
-  l11:;	
-  {  int yypos12= yy->__pos, yythunkpos12= yy->__thunkpos;
-  {  int yypos13= yy->__pos, yythunkpos13= yy->__thunkpos;  if (!yymatchChar(yy, ']')) goto l13;  goto l12;
-  l13:;	  yy->__pos= yypos13; yy->__thunkpos= yythunkpos13;
-  }  if (!yy_string(yy)) goto l12;  goto l11;
-  l12:;	  yy->__pos= yypos12; yy->__thunkpos= yythunkpos12;
+  l13:;	
+  {  int yypos14= yy->__pos, yythunkpos14= yy->__thunkpos;
+  {  int yypos15= yy->__pos, yythunkpos15= yy->__thunkpos;  if (!yymatchChar(yy, ']')) goto l15;  goto l14;
+  l15:;	  yy->__pos= yypos15; yy->__thunkpos= yythunkpos15;
+  }  if (!yy_string(yy)) goto l14;  goto l13;
+  l14:;	  yy->__pos= yypos14; yy->__thunkpos= yythunkpos14;
   }  yyText(yy, yy->__begin, yy->__end);  {
 #define yytext yy->__text
 #define yyleng yy->__textlen
-if (!(YY_END)) goto l10;
+if (!(YY_END)) goto l12;
 #undef yytext
 #undef yyleng
-  }  if (!yymatchChar(yy, ']')) goto l10;  yyDo(yy, yy_1_class, yy->__begin, yy->__end);  if (!yy__(yy)) goto l10;
+  }  if (!yymatchChar(yy, ']')) goto l12;  yyDo(yy, yy_1_class, yy->__begin, yy->__end);  if (!yy__(yy)) goto l12;
   yyprintf((stderr, "  ok   %s @ %s\n", "class", yy->__buf+yy->__pos));
   return 1;
-  l10:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  l12:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
   yyprintf((stderr, "  fail %s @ %s\n", "class", yy->__buf+yy->__pos));
   return 0;
 }
 YY_RULE(int) yy_string(yycontext *yy)
 {  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;
-  yyprintf((stderr, "%s\n", "string"));  if (!yymatchChar(yy, '"')) goto l14;  yyText(yy, yy->__begin, yy->__end);  {
+  yyprintf((stderr, "%s\n", "string"));  if (!yymatchChar(yy, '"')) goto l16;  yyText(yy, yy->__begin, yy->__end);  {
 #define yytext yy->__text
 #define yyleng yy->__textlen
-if (!(YY_BEGIN)) goto l14;
+if (!(YY_BEGIN)) goto l16;
 #undef yytext
 #undef yyleng
   }
-  l15:;	
-  {  int yypos16= yy->__pos, yythunkpos16= yy->__thunkpos;  if (!yymatchClass(yy, (unsigned char *)"\377\377\377\377\373\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377")) goto l16;  goto l15;
-  l16:;	  yy->__pos= yypos16; yy->__thunkpos= yythunkpos16;
+  l17:;	
+  {  int yypos18= yy->__pos, yythunkpos18= yy->__thunkpos;  if (!yymatchClass(yy, (unsigned char *)"\377\377\377\377\373\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377\377")) goto l18;  goto l17;
+  l18:;	  yy->__pos= yypos18; yy->__thunkpos= yythunkpos18;
   }  yyText(yy, yy->__begin, yy->__end);  {
 #define yytext yy->__text
 #define yyleng yy->__textlen
-if (!(YY_END)) goto l14;
+if (!(YY_END)) goto l16;
 #undef yytext
 #undef yyleng
-  }  if (!yymatchChar(yy, '"')) goto l14;  yyDo(yy, yy_1_string, yy->__begin, yy->__end);  if (!yy__(yy)) goto l14;
+  }  if (!yymatchChar(yy, '"')) goto l16;  yyDo(yy, yy_1_string, yy->__begin, yy->__end);  if (!yy__(yy)) goto l16;
   yyprintf((stderr, "  ok   %s @ %s\n", "string", yy->__buf+yy->__pos));
   return 1;
-  l14:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  l16:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
   yyprintf((stderr, "  fail %s @ %s\n", "string", yy->__buf+yy->__pos));
   return 0;
 }
 YY_RULE(int) yy_atom(yycontext *yy)
 {  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;
   yyprintf((stderr, "%s\n", "atom"));
-  {  int yypos18= yy->__pos, yythunkpos18= yy->__thunkpos;  if (!yy_string(yy)) goto l19;  goto l18;
-  l19:;	  yy->__pos= yypos18; yy->__thunkpos= yythunkpos18;  if (!yy_class(yy)) goto l20;  goto l18;
-  l20:;	  yy->__pos= yypos18; yy->__thunkpos= yythunkpos18;  if (!yy_dot(yy)) goto l17;
+  {  int yypos20= yy->__pos, yythunkpos20= yy->__thunkpos;  if (!yy_string(yy)) goto l21;  goto l20;
+  l21:;	  yy->__pos= yypos20; yy->__thunkpos= yythunkpos20;  if (!yy_class(yy)) goto l22;  goto l20;
+  l22:;	  yy->__pos= yypos20; yy->__thunkpos= yythunkpos20;  if (!yy_dot(yy)) goto l23;  goto l20;
+  l23:;	  yy->__pos= yypos20; yy->__thunkpos= yythunkpos20;  if (!yy_rule(yy)) goto l19;
   }
-  l18:;	
+  l20:;	
   yyprintf((stderr, "  ok   %s @ %s\n", "atom", yy->__buf+yy->__pos));
   return 1;
-  l17:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  l19:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
   yyprintf((stderr, "  fail %s @ %s\n", "atom", yy->__buf+yy->__pos));
   return 0;
 }
 YY_RULE(int) yy_postfix(yycontext *yy)
 {  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;  yyDo(yy, yyPush, 1, 0);
-  yyprintf((stderr, "%s\n", "postfix"));  if (!yy_atom(yy)) goto l21;  yyDo(yy, yySet, -1, 0);
-  {  int yypos22= yy->__pos, yythunkpos22= yy->__thunkpos;
-  {  int yypos24= yy->__pos, yythunkpos24= yy->__thunkpos;  if (!yymatchChar(yy, '?')) goto l25;  if (!yy__(yy)) goto l25;  yyDo(yy, yy_1_postfix, yy->__begin, yy->__end);  goto l24;
-  l25:;	  yy->__pos= yypos24; yy->__thunkpos= yythunkpos24;  if (!yymatchChar(yy, '*')) goto l26;  if (!yy__(yy)) goto l26;  yyDo(yy, yy_2_postfix, yy->__begin, yy->__end);  goto l24;
-  l26:;	  yy->__pos= yypos24; yy->__thunkpos= yythunkpos24;  if (!yymatchChar(yy, '+')) goto l22;  if (!yy__(yy)) goto l22;  yyDo(yy, yy_3_postfix, yy->__begin, yy->__end);
+  yyprintf((stderr, "%s\n", "postfix"));  if (!yy_atom(yy)) goto l24;  yyDo(yy, yySet, -1, 0);
+  {  int yypos25= yy->__pos, yythunkpos25= yy->__thunkpos;
+  {  int yypos27= yy->__pos, yythunkpos27= yy->__thunkpos;  if (!yymatchChar(yy, '?')) goto l28;  if (!yy__(yy)) goto l28;  yyDo(yy, yy_1_postfix, yy->__begin, yy->__end);  goto l27;
+  l28:;	  yy->__pos= yypos27; yy->__thunkpos= yythunkpos27;  if (!yymatchChar(yy, '*')) goto l29;  if (!yy__(yy)) goto l29;  yyDo(yy, yy_2_postfix, yy->__begin, yy->__end);  goto l27;
+  l29:;	  yy->__pos= yypos27; yy->__thunkpos= yythunkpos27;  if (!yymatchChar(yy, '+')) goto l25;  if (!yy__(yy)) goto l25;  yyDo(yy, yy_3_postfix, yy->__begin, yy->__end);
   }
-  l24:;	  goto l23;
-  l22:;	  yy->__pos= yypos22; yy->__thunkpos= yythunkpos22;
+  l27:;	  goto l26;
+  l25:;	  yy->__pos= yypos25; yy->__thunkpos= yythunkpos25;
   }
-  l23:;	  yyDo(yy, yy_4_postfix, yy->__begin, yy->__end);
+  l26:;	  yyDo(yy, yy_4_postfix, yy->__begin, yy->__end);
   yyprintf((stderr, "  ok   %s @ %s\n", "postfix", yy->__buf+yy->__pos));  yyDo(yy, yyPop, 1, 0);
   return 1;
-  l21:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  l24:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
   yyprintf((stderr, "  fail %s @ %s\n", "postfix", yy->__buf+yy->__pos));
   return 0;
 }
 YY_RULE(int) yy_prefix(yycontext *yy)
 {  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;  yyDo(yy, yyPush, 1, 0);
   yyprintf((stderr, "%s\n", "prefix"));
-  {  int yypos28= yy->__pos, yythunkpos28= yy->__thunkpos;  if (!yymatchChar(yy, '!')) goto l29;  if (!yy__(yy)) goto l29;  if (!yy_postfix(yy)) goto l29;  yyDo(yy, yySet, -1, 0);  yyDo(yy, yy_1_prefix, yy->__begin, yy->__end);  goto l28;
-  l29:;	  yy->__pos= yypos28; yy->__thunkpos= yythunkpos28;  if (!yy_postfix(yy)) goto l27;  yyDo(yy, yySet, -1, 0);  yyDo(yy, yy_2_prefix, yy->__begin, yy->__end);
+  {  int yypos31= yy->__pos, yythunkpos31= yy->__thunkpos;  if (!yymatchChar(yy, '!')) goto l32;  if (!yy__(yy)) goto l32;  if (!yy_postfix(yy)) goto l32;  yyDo(yy, yySet, -1, 0);  yyDo(yy, yy_1_prefix, yy->__begin, yy->__end);  goto l31;
+  l32:;	  yy->__pos= yypos31; yy->__thunkpos= yythunkpos31;  if (!yy_postfix(yy)) goto l30;  yyDo(yy, yySet, -1, 0);  yyDo(yy, yy_2_prefix, yy->__begin, yy->__end);
   }
-  l28:;	
+  l31:;	
   yyprintf((stderr, "  ok   %s @ %s\n", "prefix", yy->__buf+yy->__pos));  yyDo(yy, yyPop, 1, 0);
   return 1;
-  l27:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  l30:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
   yyprintf((stderr, "  fail %s @ %s\n", "prefix", yy->__buf+yy->__pos));
   return 0;
 }
 YY_RULE(int) yy_and(yycontext *yy)
 {  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;  yyDo(yy, yyPush, 2, 0);
   yyprintf((stderr, "%s\n", "and"));
-  {  int yypos31= yy->__pos, yythunkpos31= yy->__thunkpos;  if (!yy_prefix(yy)) goto l32;  yyDo(yy, yySet, -2, 0);  if (!yy_and(yy)) goto l32;  yyDo(yy, yySet, -1, 0);  yyDo(yy, yy_1_and, yy->__begin, yy->__end);  goto l31;
-  l32:;	  yy->__pos= yypos31; yy->__thunkpos= yythunkpos31;  if (!yy_prefix(yy)) goto l30;  yyDo(yy, yySet, -2, 0);  yyDo(yy, yy_2_and, yy->__begin, yy->__end);
+  {  int yypos34= yy->__pos, yythunkpos34= yy->__thunkpos;  if (!yy_prefix(yy)) goto l35;  yyDo(yy, yySet, -2, 0);  if (!yy_and(yy)) goto l35;  yyDo(yy, yySet, -1, 0);  yyDo(yy, yy_1_and, yy->__begin, yy->__end);  goto l34;
+  l35:;	  yy->__pos= yypos34; yy->__thunkpos= yythunkpos34;  if (!yy_prefix(yy)) goto l33;  yyDo(yy, yySet, -2, 0);  yyDo(yy, yy_2_and, yy->__begin, yy->__end);
   }
-  l31:;	
+  l34:;	
   yyprintf((stderr, "  ok   %s @ %s\n", "and", yy->__buf+yy->__pos));  yyDo(yy, yyPop, 2, 0);
   return 1;
-  l30:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  l33:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
   yyprintf((stderr, "  fail %s @ %s\n", "and", yy->__buf+yy->__pos));
   return 0;
 }
 YY_RULE(int) yy_or(yycontext *yy)
 {  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;  yyDo(yy, yyPush, 2, 0);
   yyprintf((stderr, "%s\n", "or"));
-  {  int yypos34= yy->__pos, yythunkpos34= yy->__thunkpos;  if (!yy_and(yy)) goto l35;  yyDo(yy, yySet, -2, 0);  if (!yy__(yy)) goto l35;  if (!yymatchChar(yy, '|')) goto l35;  if (!yy__(yy)) goto l35;  if (!yy_or(yy)) goto l35;  yyDo(yy, yySet, -1, 0);  yyDo(yy, yy_1_or, yy->__begin, yy->__end);  goto l34;
-  l35:;	  yy->__pos= yypos34; yy->__thunkpos= yythunkpos34;  if (!yy_and(yy)) goto l33;  yyDo(yy, yySet, -2, 0);  yyDo(yy, yy_2_or, yy->__begin, yy->__end);
+  {  int yypos37= yy->__pos, yythunkpos37= yy->__thunkpos;  if (!yy_and(yy)) goto l38;  yyDo(yy, yySet, -2, 0);  if (!yy__(yy)) goto l38;  if (!yymatchChar(yy, '|')) goto l38;  if (!yy__(yy)) goto l38;  if (!yy_or(yy)) goto l38;  yyDo(yy, yySet, -1, 0);  yyDo(yy, yy_1_or, yy->__begin, yy->__end);  goto l37;
+  l38:;	  yy->__pos= yypos37; yy->__thunkpos= yythunkpos37;  if (!yy_and(yy)) goto l36;  yyDo(yy, yySet, -2, 0);  yyDo(yy, yy_2_or, yy->__begin, yy->__end);
   }
-  l34:;	
+  l37:;	
   yyprintf((stderr, "  ok   %s @ %s\n", "or", yy->__buf+yy->__pos));  yyDo(yy, yyPop, 2, 0);
   return 1;
-  l33:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  l36:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
   yyprintf((stderr, "  fail %s @ %s\n", "or", yy->__buf+yy->__pos));
   return 0;
 }
 YY_RULE(int) yy__(yycontext *yy)
 {
   yyprintf((stderr, "%s\n", "_"));
-  l37:;	
-  {  int yypos38= yy->__pos, yythunkpos38= yy->__thunkpos;  if (!yy_space(yy)) goto l38;  goto l37;
-  l38:;	  yy->__pos= yypos38; yy->__thunkpos= yythunkpos38;
+  l40:;	
+  {  int yypos41= yy->__pos, yythunkpos41= yy->__thunkpos;  if (!yy_space(yy)) goto l41;  goto l40;
+  l41:;	  yy->__pos= yypos41; yy->__thunkpos= yythunkpos41;
   }
   yyprintf((stderr, "  ok   %s @ %s\n", "_", yy->__buf+yy->__pos));
   return 1;
 }
+YY_RULE(int) yy_id(yycontext *yy)
+{  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;
+  yyprintf((stderr, "%s\n", "id"));  yyText(yy, yy->__begin, yy->__end);  {
+#define yytext yy->__text
+#define yyleng yy->__textlen
+if (!(YY_BEGIN)) goto l42;
+#undef yytext
+#undef yyleng
+  }  if (!yymatchClass(yy, (unsigned char *)"\000\000\000\000\000\000\000\000\376\377\377\377\377\377\377\007\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000")) goto l42;
+  l43:;	
+  {  int yypos44= yy->__pos, yythunkpos44= yy->__thunkpos;  if (!yymatchClass(yy, (unsigned char *)"\000\000\000\000\000\000\377\003\376\377\377\377\377\377\377\007\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000")) goto l44;  goto l43;
+  l44:;	  yy->__pos= yypos44; yy->__thunkpos= yythunkpos44;
+  }  yyText(yy, yy->__begin, yy->__end);  {
+#define yytext yy->__text
+#define yyleng yy->__textlen
+if (!(YY_END)) goto l42;
+#undef yytext
+#undef yyleng
+  }  if (!yy__(yy)) goto l42;  yyDo(yy, yy_1_id, yy->__begin, yy->__end);
+  yyprintf((stderr, "  ok   %s @ %s\n", "id", yy->__buf+yy->__pos));
+  return 1;
+  l42:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  yyprintf((stderr, "  fail %s @ %s\n", "id", yy->__buf+yy->__pos));
+  return 0;
+}
+YY_RULE(int) yy_declaration(yycontext *yy)
+{  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;  yyDo(yy, yyPush, 2, 0);
+  yyprintf((stderr, "%s\n", "declaration"));  if (!yy_id(yy)) goto l45;  yyDo(yy, yySet, -2, 0);  if (!yymatchChar(yy, '=')) goto l45;  if (!yy__(yy)) goto l45;  if (!yy_expression(yy)) goto l45;  yyDo(yy, yySet, -1, 0);  yyDo(yy, yy_1_declaration, yy->__begin, yy->__end);
+  yyprintf((stderr, "  ok   %s @ %s\n", "declaration", yy->__buf+yy->__pos));  yyDo(yy, yyPop, 2, 0);
+  return 1;
+  l45:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  yyprintf((stderr, "  fail %s @ %s\n", "declaration", yy->__buf+yy->__pos));
+  return 0;
+}
 YY_RULE(int) yy_start(yycontext *yy)
-{  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;  yyDo(yy, yyPush, 1, 0);
-  yyprintf((stderr, "%s\n", "start"));  if (!yy__(yy)) goto l39;  if (!yy_or(yy)) goto l39;  yyDo(yy, yySet, -1, 0);  yyDo(yy, yy_1_start, yy->__begin, yy->__end);
-  yyprintf((stderr, "  ok   %s @ %s\n", "start", yy->__buf+yy->__pos));  yyDo(yy, yyPop, 1, 0);
+{  int yypos0= yy->__pos, yythunkpos0= yy->__thunkpos;
+  yyprintf((stderr, "%s\n", "start"));  if (!yy_declaration(yy)) goto l46;
+  l47:;	
+  {  int yypos48= yy->__pos, yythunkpos48= yy->__thunkpos;  if (!yy_declaration(yy)) goto l48;  goto l47;
+  l48:;	  yy->__pos= yypos48; yy->__thunkpos= yythunkpos48;
+  }
+  yyprintf((stderr, "  ok   %s @ %s\n", "start", yy->__buf+yy->__pos));
   return 1;
-  l39:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
+  l46:;	  yy->__pos= yypos0; yy->__thunkpos= yythunkpos0;
   yyprintf((stderr, "  fail %s @ %s\n", "start", yy->__buf+yy->__pos));
   return 0;
 }
@@ -908,18 +1143,12 @@ YY_PARSE(yycontext *) YYRELEASE(yycontext *yyctx)
 }
 
 #endif
-#line 205 "parse.leg"
+#line 359 "parse.leg"
+
+
 
 
-Node *_checktype(Node *object, enum op type)
-{
-    if (object->type == type) return object;
-    fprintf(stderr, "\naccesing type %i as if it were a %i\n", object->type, type);
-    exit(1);
-    return 0;
-}
 
-#define get(object, type, member)	(_checktype(object, type)->type.member)
 
 int execute(Node *node, InputBuffer *in)
 {
@@ -989,6 +1218,10 @@ int execute(Node *node, InputBuffer *in)
       advance(in, 1);
       return 1;
       }
+      case Id: {
+        Symbol *symbol= get(node, Id, symbol);
+        return execute(symbol->rule, in);
+      }
     }
     printf("this cannot happen\n");
     abort();
diff --git a/parse.leg b/parse.leg
index 4c6ee4f..fb91ec1 100644
--- a/parse.leg
+++ b/parse.leg
@@ -5,10 +5,17 @@
 #include <stdlib.h>
 #include "inputBuffer.c"
 ;
-enum op { String, Query, Star, Plus, Or, And, Class, Dot, Exc } ;
+enum op { String, Query, Star, Plus, Or, And, Class, Dot, Exc, Id } ;
 
 
 typedef union Node Node;
+typedef struct Symbol Symbol;
+typedef struct Array Array;
+typedef struct SymbolTable SymbolTable;
+struct Array {
+    Node **elements;
+    int length;
+};
 
 struct String  { enum op type;  char *string; int len; };
 struct Query   { enum op type;  Node *children[1]; };
@@ -17,8 +24,9 @@ struct Plus    { enum op type;  Node *children[1]; };
 struct Or      { enum op type;  Node *children[2]; };
 struct And     { enum op type;  Node *children[2]; };
 struct Class   { enum op type;  char *stringValue; int len; };
-struct Dot     { enum op type;};
+struct Dot     { enum op type; };
 struct Exc     { enum op type;  Node *children[1]; };
+struct Id      { enum op type; Symbol *symbol; };
 
 union Node {
     enum op type;
@@ -31,8 +39,30 @@ union Node {
     struct Class Class;
     struct Dot Dot;
     struct Exc Exc;
+    struct Id Id;
+};
+
+struct Symbol{
+  char* name;
+  Node *rule;
+};
+
+struct SymbolTable {
+    Symbol **elements;
+    int length;
 };
 
+#define SymbolTable_initialiser {0,0}
+SymbolTable symbolTable= SymbolTable_initialiser;
+
+Symbol *createSymbol(char *name) {
+    Symbol *symbol= calloc(1, sizeof(Symbol));
+    symbol->name= strdup(name);
+    return symbol;
+}
+
+
+
 
 #define new(type)			mkNode(sizeof(struct type),type)
 
@@ -51,6 +81,15 @@ Node *mkString(char *s)
     return node;
 }
 
+Node *mkId(char *s){
+  
+    Node *node= new(Id);
+    node->Id.symbol=createSymbol(s);
+    return node;
+}
+
+
+
 Node *mkQuery(Node *n)
 {
     Node *node= new(Query);
@@ -109,6 +148,16 @@ Node *mkExc(Node *n)
     return node;
 }
 
+Node *_checktype(Node *object, enum op type)
+{
+    if (object->type == type) return object;
+    fprintf(stderr, "\naccesing type %i as if it were a %i\n", object->type, type);
+    exit(1);
+    return 0;
+}
+
+#define get(object, type, member)	(_checktype(object, type)->type.member)
+
 void print(Node *node)
 {
     switch (node->type) {
@@ -147,6 +196,9 @@ void print(Node *node)
         printf("!");
         print(node->Exc.children[0]);
         return;   
+      case Id:
+        printf("%s\n",get(node,Id,symbol)->name);
+        return;
     }
     abort();
 }
@@ -168,12 +220,110 @@ else { \
     result=1; \
 }} 
 
+
+
+void move(SymbolTable *symbolTable, int a) {
+    symbolTable->length++;
+    symbolTable->elements= realloc(symbolTable->elements,sizeof(Node*) * symbolTable->length);
+    printf("begin\n");
+    for (int i= symbolTable->length-1; i >a; i--) {
+        symbolTable->elements[i] = symbolTable->elements[i-1];
+        printf("\n");
+        for(int i= 0; i<symbolTable->length; i++) {
+            printf("number : %i, name : %s, value : a\n",i, symbolTable->elements[i]->name);
+        }
+    }
+    printf("end\n");
+}
+
+void addSymbolSorted(SymbolTable *symbolTable, Symbol *symbol) {
+    int a=0;
+    int b= symbolTable->length-1;
+    int c;
+    //1 <b-a => no infinite loop with a and c = 0 et b =1
+    while (1 < b - a ) {
+        c= (a+b)/2;
+        if (strcmp(symbolTable->elements[c]->name, symbol->name) < 0) {
+            a= c;
+        } else {
+            b= c;
+        }
+    }
+    //b>-1 <=> symboleTable->length > 0
+    // this if is here to know if we put the symbol before or after a
+    if (b>-1 && strcmp(symbolTable->elements[a]->name, symbol->name) < 0) {
+        a++;
+    }
+    //we move all the symbols after a
+    move(symbolTable, a);
+    //we put the symbol at the right place
+    symbolTable->elements[a]->name = symbol->name;
+}
+
+int findSymbol(SymbolTable *symbolTable, char *name) {
+    for (int i= 0; i < symbolTable->length;i++) {
+        if (strcmp(symbolTable->elements[i]->name, name) == 0) {
+            return 1;
+        }
+    }
+    Symbol *symbol = createSymbol(name);
+    addSymbolSorted(symbolTable, symbol);
+    return 0;
+}
+
+Node *findSymbolSorted(SymbolTable *symbolTable, char *name) {
+    int a=0;
+    int b= symbolTable->length-1;
+    int c;
+    //1 <b-a => no infinite loop with a and c = 0 et b =1
+    while (1 < b - a ) {
+        c= (a+b)/2;
+        if (strcmp(symbolTable->elements[c]->name, name) < 0) {
+            a= c;
+        } else {
+            if (strcmp(symbolTable->elements[c]->name, name) > 0) {
+                b= c;
+            } else {
+                return symbolTable->elements[c]->rule;
+            }
+        }
+    }
+    //b>-1 <=> symboleTable->length > 0
+    // this if is here to know if we put the symbol before or after a
+    if (b>-1 && strcmp(symbolTable->elements[a]->name, name) < 0) {
+        a++;
+    }
+    //we move all the symbols after a
+    move(symbolTable, a);
+    //we put the symbol at the right place
+    symbolTable->elements[a]= createSymbol(name);
+    return 0;
+}
+
+void setRule(SymbolTable *symbolTable, char *name, Node *rule) {
+    for (int i= 0; i < symbolTable->length;i++) {
+        if (strcmp(symbolTable->elements[i]->name, name) == 0) {
+            symbolTable->elements[i]->rule= rule;
+            break;
+        }
+    }
+}
+
+void arrayAppend(Array *array, Node *statement) {
+    array->length++;
+    array->elements= realloc(array->elements,sizeof(Node*) * array->length);
+    array->elements[array->length-1] = statement;
+    }
+
+
 #define YYSTYPE Node *
 YYSTYPE yylval = 0;
 
 %}
 
-start	= - o:or		{ yylval = o }
+start = declaration+
+
+declaration = i:id '=' - e:expression { setRule(&symbolTable,get(i, Id, symbol)->name, e) }
 
 or	= a:and - "|" - o:or	{$$ = mkOr(o, a) }
 	| a:and			{ $$ = a }
@@ -189,7 +339,11 @@ postfix	= s:atom ( "?" -	{ s = mkQuery(s) }
 		 | "+" -	{ s = mkPlus(s) }
 		 )?		{ $$ = s}
 
-atom    = string | class | dot
+atom    = string | class | dot | rule
+
+rule = i:id !'='        { $$ = mkId(yytext) }
+
+id = < [a-zA-z_][a-zA-z_0-9]* > - { $$ = mkId(yytext) }
 
 string	= '"' < [^"]* > '"'     { $$ = mkString(yytext) } -
 
@@ -204,15 +358,9 @@ space	= [ \t] | '\n' '\r'* | '\r' '\n'*
 
 %%
 
-Node *_checktype(Node *object, enum op type)
-{
-    if (object->type == type) return object;
-    fprintf(stderr, "\naccesing type %i as if it were a %i\n", object->type, type);
-    exit(1);
-    return 0;
-}
 
-#define get(object, type, member)	(_checktype(object, type)->type.member)
+
+
 
 int execute(Node *node, InputBuffer *in)
 {
@@ -282,6 +430,10 @@ int execute(Node *node, InputBuffer *in)
       advance(in, 1);
       return 1;
       }
+      case Id: {
+        Symbol *symbol= get(node, Id, symbol);
+        return execute(symbol->rule, in);
+      }
     }
     printf("this cannot happen\n");
     abort();