diff --git a/lexer.mll b/lexer.mll
index 44e5bc3..56e3374 100644
--- a/lexer.mll
+++ b/lexer.mll
@@ -17,7 +17,12 @@ rule token = parse
   | "elim"                      { ELIM }
   | "cut"                       { CUT }
   | "False"                     { FALSE }
-  
+
+  | "fun"                       { FUN }
+  | "=>"                        { MAPS_TO }
+  | ':'                         { VDOTS }
+  | "exf"                       { EXF }
+
   | ['A'-'Z']+['0'-'9']* as s   { TYPE_NAME s }
   | ['a'-'z']+['0'-'9']* as s   { VAR_NAME s }
   | '.'                         { DOT }
diff --git a/main.ml b/main.ml
index 94ea82f..d4c3d17 100644
--- a/main.ml
+++ b/main.ml
@@ -37,6 +37,24 @@ let readline () = match file with
   | Some f -> input_line f
 in
 
+if !reduce_option then (
+    let lexbuf = Lexing.from_channel (match file with
+      | None -> stdin
+      | Some file -> file
+    )
+    in
+    let lambda_term =
+        try
+            Parser.main_lambda Lexer.token lexbuf
+        with e -> (
+            Printf.printf "Can't read lambda term\n";
+            raise e
+       )
+    in
+    reduce lambda_term;
+    exit 0
+);
+
 (* Show a message only if the input is read from stdin *)
 let show s = match file with
   | None -> Printf.printf "%s" s
diff --git a/parser.mly b/parser.mly
index 9214cae..b5e1710 100644
--- a/parser.mly
+++ b/parser.mly
@@ -11,6 +11,7 @@
 %token <string> TYPE_NAME
 
 %token DOT INTRO ASSUMPTION APPLY ELIM CUT
+%token FUN MAPS_TO VDOTS EXF
 
 /* L'ordre de définition définit la priorité */
 %right RARROW
@@ -22,10 +23,20 @@
 %start main_tactic
 %type <Tactic.tactic> main_tactic
 
+%start main_lambda
+%type <Structs.lam> main_lambda
+
 %%
 main_type:
   | ty EOF                                { $1 }
 
+main_tactic:
+  | tactic EOF                            { $1 }
+
+main_lambda:
+  | lambda EOF                            { $1 }
+
+/* Types */
 ty:
   | LPAREN ty RPAREN                      { $2 }
   | ty RARROW ty                          { TImpl ($1, $3) }
@@ -33,12 +44,27 @@ ty:
   | TILDE ty                              { TImpl ($2, TFalse) }
   | FALSE                                 { TFalse }
 
-main_tactic:
-  | tactic EOF                            { $1 }
-
+/* Tactiques */
 tactic:
   | INTRO VAR_NAME DOT                    { Intro $2 }
   | ASSUMPTION DOT                        { Assumption }
   | APPLY VAR_NAME DOT                    { Apply $2 }
   | ELIM VAR_NAME DOT                     { Elim $2 }
   | CUT ty DOT                            { Cut $2 }
+
+/* Lambda-termes */
+lambda_arg: /* Expression pouvant être en argument d'une fonction */
+  | VAR_NAME                              { LVar $1 }
+  | LPAREN lambda RPAREN                  { $2 }
+
+/* Application d'une fonction */
+lambda_app:
+  | lambda_app lambda_arg                 { LApp ($1, $2) }
+  | lambda_arg                            { $1 }
+
+lambda:
+  | lambda_app                            { $1 }
+  | FUN VAR_NAME VDOTS ty MAPS_TO lambda  { LFun ($2, $4, $6) }
+  | FUN LPAREN VAR_NAME VDOTS ty RPAREN MAPS_TO lambda
+                                          { LFun ($3, $5, $8) }
+  | EXF LPAREN VAR_NAME VDOTS ty RPAREN   { LExf (LVar $3, $5) }