From 623683839fb1f33714ff3dba88c58841f3702bb8 Mon Sep 17 00:00:00 2001
From: Christian Rinderknecht <Christian.Rinderknecht@tezcore.com>
Date: Mon, 18 Mar 2019 17:47:11 +0100
Subject: [PATCH] Removed keyword "null", replaced by two keywords "do" and
 "nothing".

Until now only products of type names were allowed: I extended
them to allow type expressions.

Removed the destructive update of a map binding "a[b] := c".

Record projection has been extended to allow for qualified
names: "a.b.c" and "a.b.c[d]".

Changed the LIGO extension from ".li" to ".ligo".

Fixed the name of the language to be "LIGO" (instead of "Ligo").
---
 AST.ml                                       | 211 +++++++++----------
 AST.mli                                      | 124 +++++------
 EvalOpt.ml                                   |  10 +-
 EvalOpt.mli                                  |   4 +-
 LexToken.mli                                 |   5 +-
 LexToken.mll                                 |  18 +-
 Lexer.mli                                    |   8 +-
 Lexer.mll                                    |  10 +-
 LexerMain.ml                                 |   2 +-
 Markup.mli                                   |   2 +-
 ParToken.mly                                 |   3 +-
 Parser.mly                                   | 118 ++++++-----
 ParserMain.ml                                |   6 +-
 Tests/{Crowdfunding.li => crowdfunding.ligo} |  48 +++--
 14 files changed, 290 insertions(+), 279 deletions(-)
 rename Tests/{Crowdfunding.li => crowdfunding.ligo} (53%)

diff --git a/AST.ml b/AST.ml
index bd92bfaab..0d9fdeee5 100644
--- a/AST.ml
+++ b/AST.ml
@@ -1,4 +1,4 @@
-(* Abstract Syntax Tree (AST) for Ligo *)
+(* Abstract Syntax Tree (AST) for LIGO *)
 
 (* To disable warning about multiply-defined record labels. *)
 
@@ -37,7 +37,7 @@ let sepseq_to_region to_region = function
       None -> Region.ghost
 | Some seq -> nsepseq_to_region to_region seq
 
-(* Keywords of Ligo *)
+(* Keywords of LIGO *)
 
 type kwd_begin      = Region.t
 type kwd_const      = Region.t
@@ -55,7 +55,6 @@ type kwd_is         = Region.t
 type kwd_match      = Region.t
 type kwd_mod        = Region.t
 type kwd_not        = Region.t
-type kwd_null       = Region.t
 type kwd_of         = Region.t
 type kwd_procedure  = Region.t
 type kwd_record     = Region.t
@@ -89,7 +88,7 @@ type rbracket = Region.t
 type cons     = Region.t
 type vbar     = Region.t
 type arrow    = Region.t
-type ass      = Region.t
+type assign   = Region.t
 type equal    = Region.t
 type colon    = Region.t
 type bool_or  = Region.t
@@ -208,7 +207,7 @@ and field_decl = {
   field_type : type_expr
 }
 
-and type_tuple = (type_name, comma) nsepseq par reg
+and type_tuple = (type_expr, comma) nsepseq par reg
 
 (* Function and procedure declarations *)
 
@@ -306,7 +305,7 @@ and var_decl = {
   name       : variable;
   colon      : colon;
   var_type   : type_expr;
-  ass        : ass;
+  assign     : assign;
   init       : expr;
   terminator : semi option
 }
@@ -318,13 +317,13 @@ and instruction =
 | Block  of block reg
 
 and single_instr =
-  Cond     of conditional reg
-| Match    of match_instr reg
-| Ass      of ass_instr
-| Loop     of loop
-| ProcCall of fun_call
-| Null     of kwd_null
-| Fail     of fail_instr reg
+  Cond      of conditional reg
+| Match     of match_instr reg
+| Assign    of assignment reg
+| Loop      of loop
+| ProcCall  of fun_call
+| Fail      of fail_instr reg
+| DoNothing of Region.t
 
 and fail_instr = {
   kwd_fail  : kwd_fail;
@@ -357,19 +356,9 @@ and case = {
   instr   : instruction
 }
 
-and ass_instr =
-  VarAss of var_ass reg
-| MapAss of map_ass reg
-
-and var_ass = {
-  var  : variable;
-  ass  : ass;
-  expr : expr
-}
-
-and map_ass = {
-  lookup : map_lookup reg;
-  ass    : ass;
+and assignment = {
+  var    : variable;
+  assign : assign;
   expr   : expr
 }
 
@@ -389,7 +378,7 @@ and for_loop =
 
 and for_int = {
   kwd_for : kwd_for;
-  var_ass : var_ass reg;
+  assign  : assignment reg;
   down    : kwd_down option;
   kwd_to  : kwd_to;
   bound   : expr;
@@ -429,21 +418,21 @@ and logic_expr =
 | CompExpr of comp_expr
 
 and bool_expr =
-  Or    of bool_or bin_op reg
+  Or    of bool_or  bin_op reg
 | And   of bool_and bin_op reg
-| Not   of kwd_not un_op reg
+| Not   of kwd_not   un_op reg
 | False of c_False
 | True  of c_True
 
 and 'a bin_op = {
-  op1 : expr;
-  op  : 'a;
-  op2 : expr
+  op   : 'a;
+  arg1 : expr;
+  arg2 : expr
 }
 
 and 'a un_op = {
   op  : 'a;
-  op1 : expr
+  arg : expr
 }
 
 and comp_expr =
@@ -460,7 +449,7 @@ and arith_expr =
 | Mult of times   bin_op reg
 | Div  of slash   bin_op reg
 | Mod  of kwd_mod bin_op reg
-| Neg  of minus   un_op reg
+| Neg  of minus    un_op reg
 | Int  of (Lexer.lexeme * Z.t) reg
 
 and string_expr =
@@ -488,12 +477,12 @@ and record_expr =
 
 and record_injection = {
   opening    : kwd_record;
-  fields     : (field_ass reg, semi) nsepseq;
+  fields     : (field_assign reg, semi) nsepseq;
   terminator : semi option;
   close      : kwd_end
 }
 
-and field_ass = {
+and field_assign = {
   field_name : field_name;
   equal      : equal;
   field_expr : expr
@@ -502,7 +491,7 @@ and field_ass = {
 and record_projection = {
   record_name : variable;
   selector    : dot;
-  field_name  : field_name
+  field_path  : (field_name, dot) nsepseq
 }
 
 and record_copy = {
@@ -545,11 +534,14 @@ and fun_call = (fun_name * arguments) reg
 and arguments = tuple
 
 and map_lookup = {
-  map_name : variable;
-  selector : dot;
+  map_path : map_path;
   index    : expr brackets reg
 }
 
+and map_path =
+  Map     of map_name
+| MapPath of record_projection reg
+
 (* Patterns *)
 
 and pattern =
@@ -653,13 +645,12 @@ and record_expr_to_region = function
 let instr_to_region = function
   Single Cond                {region; _}
 | Single Match               {region; _}
-| Single Ass VarAss          {region; _}
-| Single Ass MapAss          {region; _}
+| Single Assign              {region; _}
 | Single Loop While          {region; _}
 | Single Loop For ForInt     {region; _}
 | Single Loop For ForCollect {region; _}
 | Single ProcCall            {region; _}
-| Single Null                 region
+| Single DoNothing            region
 | Single Fail                {region; _}
 | Block                      {region; _} -> region
 
@@ -812,7 +803,7 @@ and print_field_decl {value; _} =
 and print_type_tuple {value; _} =
   let {lpar; inside; rpar} = value in
   print_token lpar "(";
-  print_nsepseq "," print_var inside;
+  print_nsepseq "," print_type_expr inside;
   print_token rpar ")"
 
 and print_lambda_decl = function
@@ -922,12 +913,12 @@ and print_local_decl = function
 
 and print_var_decl {value; _} =
   let {kwd_var; name; colon; var_type;
-       ass; init; terminator} = value in
+       assign; init; terminator} = value in
   print_token      kwd_var "var";
   print_var        name;
   print_token      colon ":";
   print_type_expr  var_type;
-  print_token      ass ":=";
+  print_token      assign ":=";
   print_expr       init;
   print_terminator terminator
 
@@ -941,11 +932,11 @@ and print_instruction = function
 and print_single_instr = function
   Cond     {value; _} -> print_conditional value
 | Match    {value; _} -> print_match_instr value
-| Ass      instr      -> print_ass_instr instr
+| Assign   assign     -> print_assignment assign
 | Loop     loop       -> print_loop loop
 | ProcCall fun_call   -> print_fun_call fun_call
-| Null     kwd_null   -> print_token kwd_null "null"
 | Fail     {value; _} -> print_fail value
+| DoNothing region    -> print_token region "do nothing"
 
 and print_fail {kwd_fail; fail_expr} =
   print_token kwd_fail "fail";
@@ -984,20 +975,10 @@ and print_case {value; _} =
   print_token arrow "->";
   print_instruction instr
 
-and print_ass_instr = function
-  VarAss a -> print_var_ass a
-| MapAss a -> print_map_ass a
-
-and print_var_ass {value; _} =
-  let {var; ass; expr} = value in
+and print_assignment {value; _} =
+  let {var; assign; expr} = value in
   print_var var;
-  print_token ass ":=";
-  print_expr expr
-
-and print_map_ass {value; _} =
-  let {lookup; ass; expr} = value in
-  print_map_lookup lookup;
-  print_token ass ":=";
+  print_token assign ":=";
   print_expr expr
 
 and print_loop = function
@@ -1015,15 +996,15 @@ and print_for_loop = function
 | ForCollect for_collect -> print_for_collect for_collect
 
 and print_for_int ({value; _} : for_int reg) =
-  let {kwd_for; var_ass; down; kwd_to;
+  let {kwd_for; assign; down; kwd_to;
        bound; step; block} = value in
-  print_token   kwd_for "for";
-  print_var_ass var_ass;
-  print_down    down;
-  print_token   kwd_to "to";
-  print_expr    bound;
-  print_step    step;
-  print_block   block
+  print_token      kwd_for "for";
+  print_assignment assign;
+  print_down       down;
+  print_token      kwd_to "to";
+  print_expr       bound;
+  print_step       step;
+  print_block      block
 
 and print_down = function
   Some kwd_down -> print_token kwd_down "down"
@@ -1071,52 +1052,52 @@ and print_logic_expr = function
 | CompExpr e -> print_comp_expr e
 
 and print_bool_expr = function
-  Or {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "||"; print_expr op2
-| And {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "&&"; print_expr op2
-| Not {value = {op; op1}; _} ->
-    print_token op "not"; print_expr op1
+  Or {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "||"; print_expr arg2
+| And {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "&&"; print_expr arg2
+| Not {value = {op; arg}; _} ->
+    print_token op "not"; print_expr arg
 | False region -> print_token region "False"
 | True region  -> print_token region "True"
 
 and print_comp_expr = function
-  Lt {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "<"; print_expr op2
-| Leq {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "<="; print_expr op2
-| Gt {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op ">"; print_expr op2
-| Geq {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op ">="; print_expr op2
-| Equal {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "="; print_expr op2
-| Neq {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "=/="; print_expr op2
+  Lt {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "<"; print_expr arg2
+| Leq {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "<="; print_expr arg2
+| Gt {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op ">"; print_expr arg2
+| Geq {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op ">="; print_expr arg2
+| Equal {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "="; print_expr arg2
+| Neq {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "=/="; print_expr arg2
 
 and print_arith_expr = function
-  Add {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "+"; print_expr op2
-| Sub {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "-"; print_expr op2
-| Mult {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "*"; print_expr op2
-| Div {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "/"; print_expr op2
-| Mod {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "mod"; print_expr op2
-| Neg {value = {op; op1}; _} ->
-    print_token op "-"; print_expr op1
+  Add {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "+"; print_expr arg2
+| Sub {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "-"; print_expr arg2
+| Mult {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "*"; print_expr arg2
+| Div {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "/"; print_expr arg2
+| Mod {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "mod"; print_expr arg2
+| Neg {value = {op; arg}; _} ->
+    print_token op "-"; print_expr arg
 | Int i -> print_int i
 
 and print_string_expr = function
-  Cat {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "^"; print_expr op2
+  Cat {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "^"; print_expr arg2
 | String s -> print_string s
 
 and print_list_expr = function
-  Cons {value = {op1; op; op2}; _} ->
-    print_expr op1; print_token op "#"; print_expr op2
+  Cons {value = {arg1; op; arg2}; _} ->
+    print_expr arg1; print_token op "#"; print_expr arg2
 | List e       -> print_list e
 | EmptyList e  -> print_empty_list e
 
@@ -1137,21 +1118,24 @@ and print_record_expr = function
 and print_record_injection {value; _} =
   let {opening; fields; terminator; close} = value in
   print_token opening "record";
-  print_nsepseq ";" print_field_ass fields;
+  print_nsepseq ";" print_field_assign fields;
   print_terminator terminator;
   print_token close "end"
 
-and print_field_ass {value; _} =
+and print_field_assign {value; _} =
   let {field_name; equal; field_expr} = value in
   print_var field_name;
   print_token equal "=";
   print_expr field_expr
 
 and print_record_projection {value; _} =
-  let {record_name; selector; field_name} = value in
+  let {record_name; selector; field_path} = value in
   print_var record_name;
   print_token selector ".";
-  print_var field_name
+  print_field_path field_path
+
+and print_field_path sequence =
+  print_nsepseq "." print_var sequence
 
 and print_record_copy {value; _} =
   let {kwd_copy; record_name; kwd_with; delta} = value in
@@ -1223,13 +1207,16 @@ and print_some_app {value; _} =
   print_tuple arguments
 
 and print_map_lookup {value; _} =
-  let {map_name; selector; index} = value in
+  let {map_path; index} = value in
   let {lbracket; inside; rbracket} = index.value in
-  print_var   map_name;
-  print_token selector ".";
-  print_token lbracket "[";
-  print_expr  inside;
-  print_token rbracket "]"
+  print_map_path map_path;
+  print_token    lbracket "[";
+  print_expr     inside;
+  print_token    rbracket "]"
+
+and print_map_path = function
+  Map map_name -> print_var map_name
+| MapPath path -> print_record_projection path
 
 and print_par_expr {value; _} =
   let {lpar; inside; rpar} = value in
diff --git a/AST.mli b/AST.mli
index ddf5a795a..305640a75 100644
--- a/AST.mli
+++ b/AST.mli
@@ -1,4 +1,4 @@
-(* Abstract Syntax Tree (AST) for Ligo *)
+(* Abstract Syntax Tree (AST) for LIGO *)
 
 [@@@warning "-30"]
 
@@ -21,7 +21,7 @@ val nseq_to_region    : ('a -> Region.t) -> 'a nseq -> Region.t
 val nsepseq_to_region : ('a -> Region.t) -> ('a,'sep) nsepseq -> Region.t
 val sepseq_to_region  : ('a -> Region.t) -> ('a,'sep) sepseq -> Region.t
 
-(* Keywords of Ligo *)
+(* Keywords of LIGO *)
 
 type kwd_begin      = Region.t
 type kwd_const      = Region.t
@@ -39,7 +39,6 @@ type kwd_is         = Region.t
 type kwd_match      = Region.t
 type kwd_mod        = Region.t
 type kwd_not        = Region.t
-type kwd_null       = Region.t
 type kwd_of         = Region.t
 type kwd_procedure  = Region.t
 type kwd_record     = Region.t
@@ -62,34 +61,34 @@ type c_Unit  = Region.t
 
 (* Symbols *)
 
-type semi     = Region.t
-type comma    = Region.t
-type lpar     = Region.t
-type rpar     = Region.t
-type lbrace   = Region.t
-type rbrace   = Region.t
-type lbracket = Region.t
-type rbracket = Region.t
-type cons     = Region.t
-type vbar     = Region.t
-type arrow    = Region.t
-type ass      = Region.t
-type equal    = Region.t
-type colon    = Region.t
-type bool_or  = Region.t
-type bool_and = Region.t
-type lt       = Region.t
-type leq      = Region.t
-type gt       = Region.t
-type geq      = Region.t
-type neq      = Region.t
-type plus     = Region.t
-type minus    = Region.t
-type slash    = Region.t
-type times    = Region.t
-type dot      = Region.t
-type wild     = Region.t
-type cat      = Region.t
+type semi     = Region.t  (* ";"   *)
+type comma    = Region.t  (* ","   *)
+type lpar     = Region.t  (* "("   *)
+type rpar     = Region.t  (* ")"   *)
+type lbrace   = Region.t  (* "{"   *)
+type rbrace   = Region.t  (* "}"   *)
+type lbracket = Region.t  (* "["   *)
+type rbracket = Region.t  (* "]"   *)
+type cons     = Region.t  (* "#"   *)
+type vbar     = Region.t  (* "|"   *)
+type arrow    = Region.t  (* "->"  *)
+type assign   = Region.t  (* ":="  *)
+type equal    = Region.t  (* "="   *)
+type colon    = Region.t  (* ":"   *)
+type bool_or  = Region.t  (* "||"  *)
+type bool_and = Region.t  (* "&&"  *)
+type lt       = Region.t  (* "<"   *)
+type leq      = Region.t  (* "<="  *)
+type gt       = Region.t  (* ">"   *)
+type geq      = Region.t  (* ">="  *)
+type neq      = Region.t  (* "=/=" *)
+type plus     = Region.t  (* "+"   *)
+type minus    = Region.t  (* "-"   *)
+type slash    = Region.t  (* "/"   *)
+type times    = Region.t  (* "*"   *)
+type dot      = Region.t  (* "."   *)
+type wild     = Region.t  (* "_"   *)
+type cat      = Region.t  (* "^"   *)
 
 (* Virtual tokens *)
 
@@ -192,7 +191,7 @@ and field_decl = {
   field_type : type_expr
 }
 
-and type_tuple = (type_name, comma) nsepseq par reg
+and type_tuple = (type_expr, comma) nsepseq par reg
 
 (* Function and procedure declarations *)
 
@@ -290,7 +289,7 @@ and var_decl = {
   name       : variable;
   colon      : colon;
   var_type   : type_expr;
-  ass        : ass;
+  assign     : assign;
   init       : expr;
   terminator : semi option
 }
@@ -302,13 +301,13 @@ and instruction =
 | Block  of block reg
 
 and single_instr =
-  Cond     of conditional reg
-| Match    of match_instr reg
-| Ass      of ass_instr
-| Loop     of loop
-| ProcCall of fun_call
-| Null     of kwd_null
-| Fail     of fail_instr reg
+  Cond      of conditional reg
+| Match     of match_instr reg
+| Assign    of assignment reg
+| Loop      of loop
+| ProcCall  of fun_call
+| Fail      of fail_instr reg
+| DoNothing of Region.t
 
 and fail_instr = {
   kwd_fail  : kwd_fail;
@@ -341,19 +340,9 @@ and case = {
   instr   : instruction
 }
 
-and ass_instr =
-  VarAss of var_ass reg
-| MapAss of map_ass reg
-
-and var_ass = {
-  var  : variable;
-  ass  : ass;
-  expr : expr
-}
-
-and map_ass = {
-  lookup : map_lookup reg;
-  ass    : ass;
+and assignment = {
+  var    : variable;
+  assign : assign;
   expr   : expr
 }
 
@@ -373,7 +362,7 @@ and for_loop =
 
 and for_int = {
   kwd_for : kwd_for;
-  var_ass : var_ass reg;
+  assign  : assignment reg;
   down    : kwd_down option;
   kwd_to  : kwd_to;
   bound   : expr;
@@ -413,21 +402,21 @@ and logic_expr =
 | CompExpr of comp_expr
 
 and bool_expr =
-  Or    of bool_or bin_op reg
+  Or    of bool_or  bin_op reg
 | And   of bool_and bin_op reg
-| Not   of kwd_not un_op reg
+| Not   of kwd_not   un_op reg
 | False of c_False
 | True  of c_True
 
 and 'a bin_op = {
-  op1 : expr;
-  op  : 'a;
-  op2 : expr
+  op   : 'a;
+  arg1 : expr;
+  arg2 : expr
 }
 
 and 'a un_op = {
   op  : 'a;
-  op1 : expr
+  arg : expr
 }
 
 and comp_expr =
@@ -444,7 +433,7 @@ and arith_expr =
 | Mult of times   bin_op reg
 | Div  of slash   bin_op reg
 | Mod  of kwd_mod bin_op reg
-| Neg  of minus   un_op reg
+| Neg  of minus    un_op reg
 | Int  of (Lexer.lexeme * Z.t) reg
 
 and string_expr =
@@ -472,12 +461,12 @@ and record_expr =
 
 and record_injection = {
   opening    : kwd_record;
-  fields     : (field_ass reg, semi) nsepseq;
+  fields     : (field_assign reg, semi) nsepseq;
   terminator : semi option;
   close      : kwd_end
 }
 
-and field_ass = {
+and field_assign = {
   field_name : field_name;
   equal      : equal;
   field_expr : expr
@@ -486,7 +475,7 @@ and field_ass = {
 and record_projection = {
   record_name : variable;
   selector    : dot;
-  field_name  : field_name
+  field_path  : (field_name, dot) nsepseq
 }
 
 and record_copy = {
@@ -529,11 +518,14 @@ and fun_call = (fun_name * arguments) reg
 and arguments = tuple
 
 and map_lookup = {
-  map_name : variable;
-  selector : dot;
+  map_path : map_path;
   index    : expr brackets reg
 }
 
+and map_path =
+  Map     of map_name
+| MapPath of record_projection reg
+
 (* Patterns *)
 
 and pattern =
diff --git a/EvalOpt.ml b/EvalOpt.ml
index 3f625b942..20d039603 100644
--- a/EvalOpt.ml
+++ b/EvalOpt.ml
@@ -1,4 +1,4 @@
-(* Parsing the command-line option for testing the Ligo lexer and
+(* Parsing the command-line option for testing the LIGO lexer and
    parser *)
 
 let  printf = Printf.printf
@@ -11,8 +11,8 @@ let abort msg =
 
 let help () =
   let file = Filename.basename Sys.argv.(0) in
-  printf "Usage: %s [<option> ...] [<input>.li | \"-\"]\n" file;
-  print_endline "where <input>.li is the Ligo source file (default: stdin),";
+  printf "Usage: %s [<option> ...] [<input>.ligo | \"-\"]\n" file;
+  print_endline "where <input>.ligo is the LIGO source file (default: stdin),";
   print_endline "and each <option> (if any) is one of the following:";
   print_endline "  -I <paths>             Library paths (colon-separated)";
   print_endline "  -c, --copy             Print lexemes of tokens and markup (lexer)";
@@ -127,11 +127,11 @@ let input =
   match !input with
     None | Some "-" -> !input
   | Some file_path ->
-      if   Filename.check_suffix file_path ".li"
+      if   Filename.check_suffix file_path ".ligo"
       then if   Sys.file_exists file_path
            then Some file_path
            else abort "Source file not found."
-      else abort "Source file lacks the extension .li."
+      else abort "Source file lacks the extension .ligo."
 
 (* Exporting remaining options as non-mutable values *)
 
diff --git a/EvalOpt.mli b/EvalOpt.mli
index dff13f7a2..b30c559f7 100644
--- a/EvalOpt.mli
+++ b/EvalOpt.mli
@@ -1,4 +1,4 @@
-(* Parsing the command-line option for testing the Ligo lexer and
+(* Parsing the command-line option for testing the LIGO lexer and
    parser *)
 
 (* If the value [offsets] is [true], then the user requested that
@@ -25,7 +25,7 @@ val verbose : Utils.String.Set.t
 
 val input : string option
 
-(* Paths where to find Ligo files for inclusion *)
+(* Paths where to find LIGO files for inclusion *)
 
 val libs : string list
 
diff --git a/LexToken.mli b/LexToken.mli
index 48b981b18..5c9c1725f 100644
--- a/LexToken.mli
+++ b/LexToken.mli
@@ -1,4 +1,4 @@
-(* This signature defines the lexical tokens for Ligo
+(* This signature defines the lexical tokens for LIGO
 
    _Tokens_ are the abstract units which are used by the parser to
    build the abstract syntax tree (AST), in other words, the stream of
@@ -70,6 +70,7 @@ type t =
 | Begin      of Region.t  (* "begin"      *)
 | Const      of Region.t  (* "const"      *)
 | Copy       of Region.t  (* "copy"       *)
+| Do         of Region.t  (* "do"         *)
 | Down       of Region.t  (* "down"       *)
 | Fail       of Region.t  (* "fail"       *)
 | If         of Region.t  (* "if"         *)
@@ -85,7 +86,7 @@ type t =
 | Then       of Region.t  (* "then"       *)
 | Else       of Region.t  (* "else"       *)
 | Match      of Region.t  (* "match"      *)
-| Null       of Region.t  (* "null"       *)
+| Nothing    of Region.t  (* "nothing"    *)
 | Procedure  of Region.t  (* "procedure"  *)
 | Record     of Region.t  (* "record"     *)
 | Step       of Region.t  (* "step"       *)
diff --git a/LexToken.mll b/LexToken.mll
index 1c78d5de2..3d311078d 100644
--- a/LexToken.mll
+++ b/LexToken.mll
@@ -1,4 +1,4 @@
-(* Lexer specification for Ligo, to be processed by [ocamllex] *)
+(* Lexer specification for LIGO, to be processed by [ocamllex] *)
 
 {
 (* START HEADER *)
@@ -69,6 +69,7 @@ type t =
 | Begin      of Region.t
 | Const      of Region.t
 | Copy       of Region.t
+| Do         of Region.t
 | Down       of Region.t
 | Fail       of Region.t
 | If         of Region.t
@@ -84,7 +85,7 @@ type t =
 | Then       of Region.t
 | Else       of Region.t
 | Match      of Region.t
-| Null       of Region.t
+| Nothing    of Region.t
 | Procedure  of Region.t
 | Record     of Region.t
 | Step       of Region.t
@@ -188,6 +189,7 @@ let proj_token = function
 | Begin      region -> region, "Begin"
 | Const      region -> region, "Const"
 | Copy       region -> region, "Copy"
+| Do         region -> region, "Do"
 | Down       region -> region, "Down"
 | Fail       region -> region, "Fail"
 | If         region -> region, "If"
@@ -203,7 +205,7 @@ let proj_token = function
 | Then       region -> region, "Then"
 | Else       region -> region, "Else"
 | Match      region -> region, "Match"
-| Null       region -> region, "Null"
+| Nothing    region -> region, "Nothing"
 | Procedure  region -> region, "Procedure"
 | Record     region -> region, "Record"
 | Step       region -> region, "Step"
@@ -272,6 +274,7 @@ let to_lexeme = function
 | Begin      _ -> "begin"
 | Const      _ -> "const"
 | Copy       _ -> "copy"
+| Do         _ -> "do"
 | Down       _ -> "down"
 | Fail       _ -> "fail"
 | If         _ -> "if"
@@ -287,7 +290,7 @@ let to_lexeme = function
 | Then       _ -> "then"
 | Else       _ -> "else"
 | Match      _ -> "match"
-| Null       _ -> "null"
+| Nothing    _ -> "nothing"
 | Procedure  _ -> "procedure"
 | Record     _ -> "record"
 | Step       _ -> "step"
@@ -324,6 +327,7 @@ let keywords = [
   (fun reg -> Begin      reg);
   (fun reg -> Const      reg);
   (fun reg -> Copy       reg);
+  (fun reg -> Do         reg);
   (fun reg -> Down       reg);
   (fun reg -> Fail       reg);
   (fun reg -> If         reg);
@@ -339,7 +343,7 @@ let keywords = [
   (fun reg -> Then       reg);
   (fun reg -> Else       reg);
   (fun reg -> Match      reg);
-  (fun reg -> Null       reg);
+  (fun reg -> Nothing    reg);
   (fun reg -> Procedure  reg);
   (fun reg -> Record     reg);
   (fun reg -> Step       reg);
@@ -359,7 +363,6 @@ let reserved =
         |> add "assert"
         |> add "class"
         |> add "constraint"
-        |> add "do"
         |> add "done"
         |> add "downto"
         |> add "exception"
@@ -548,6 +551,7 @@ let is_kwd = function
   Begin      _
 | Const      _
 | Copy       _
+| Do         _
 | Down       _
 | Fail       _
 | If         _
@@ -563,7 +567,7 @@ let is_kwd = function
 | Then       _
 | Else       _
 | Match      _
-| Null       _
+| Nothing    _
 | Procedure  _
 | Record     _
 | Step       _
diff --git a/Lexer.mli b/Lexer.mli
index 572013a14..fa0d3491b 100644
--- a/Lexer.mli
+++ b/Lexer.mli
@@ -1,16 +1,16 @@
-(* Lexer specification for Ligo, to be processed by [ocamllex].
+(* Lexer specification for LIGO, to be processed by [ocamllex].
 
    The underlying design principles are:
 
      (1) enforce stylistic constraints at a lexical level, in order to
          early reject potentially misleading or poorly written
-         Ligo contracts;
+         LIGO contracts;
 
      (2) provide precise error messages with hint as how to fix the
          issue, which is achieved by consulting the lexical
          right-context of lexemes;
 
-     (3) be as independent as possible from the Ligo version, so
+     (3) be as independent as possible from the LIGO version, so
          upgrades have as little impact as possible on this
          specification: this is achieved by using the most general
          regular expressions to match the lexing buffer and broadly
@@ -27,7 +27,7 @@
    be contextualised by the lexer in terms of input source regions, so
    useful error messages can be printed, therefore they are part of
    the signature [TOKEN] that parameterise the functor generated
-   here. For instance, if, in a future release of Ligo, new tokens may
+   here. For instance, if, in a future release of LIGO, new tokens may
    be added, and the recognition of their lexemes may entail new
    errors, the signature [TOKEN] will have to be augmented and the
    lexer specification changed. However, it is more likely that
diff --git a/Lexer.mll b/Lexer.mll
index 709c77803..b18310d55 100644
--- a/Lexer.mll
+++ b/Lexer.mll
@@ -1,4 +1,4 @@
-(* Lexer specification for Ligo, to be processed by [ocamllex]. *)
+(* Lexer specification for LIGO, to be processed by [ocamllex]. *)
 
 {
 (* START HEADER *)
@@ -231,13 +231,13 @@ module Make (Token: TOKEN) : (S with module Token = Token) =
        lexer.
 
          The state also includes a field [pos] which holds the current
-       position in the Ligo source file. The position is not always
+       position in the LIGO source file. The position is not always
        updated after a single character has been matched: that depends
        on the regular expression that matched the lexing buffer.
 
          The fields [decoder] and [supply] offer the support needed
        for the lexing of UTF-8 encoded characters in comments (the
-       only place where they are allowed in Ligo). The former is the
+       only place where they are allowed in LIGO). The former is the
        decoder proper and the latter is the effectful function
        [supply] that takes a byte, a start index and a length and feed
        it to [decoder]. See the documentation of the third-party
@@ -508,14 +508,14 @@ and scan state = parse
 
   (* Management of #include CPP directives
 
-    An input Ligo program may contain GNU CPP (C preprocessor)
+    An input LIGO program may contain GNU CPP (C preprocessor)
     directives, and the entry modules (named *Main.ml) run CPP on them
     in traditional mode:
 
     https://gcc.gnu.org/onlinedocs/cpp/Traditional-Mode.html
 
       The main interest in using CPP is that it can stand for a poor
-    man's (flat) module system for Ligo thanks to #include
+    man's (flat) module system for LIGO thanks to #include
     directives, and the traditional mode leaves the markup mostly
     undisturbed.
 
diff --git a/LexerMain.ml b/LexerMain.ml
index 14e2c431b..1280d3638 100644
--- a/LexerMain.ml
+++ b/LexerMain.ml
@@ -1,4 +1,4 @@
-(* Driver for the lexer of Ligo *)
+(* Driver for the lexer of LIGO *)
 
 open! EvalOpt (* Reads the command-line options: Effectful! *)
 
diff --git a/Markup.mli b/Markup.mli
index e43996a55..e9c525893 100644
--- a/Markup.mli
+++ b/Markup.mli
@@ -1,4 +1,4 @@
-(* This module defines the sorts of markup recognised by the Ligo
+(* This module defines the sorts of markup recognised by the LIGO
    lexer *)
 
 (* A lexeme is piece of concrete syntax belonging to a token. In
diff --git a/ParToken.mly b/ParToken.mly
index 3042595da..188505a5f 100644
--- a/ParToken.mly
+++ b/ParToken.mly
@@ -47,6 +47,7 @@
 %token <Region.t> Begin       (* "begin"      *)
 %token <Region.t> Const       (* "const"      *)
 %token <Region.t> Copy        (* "copy"       *)
+%token <Region.t> Do          (* "do"         *)
 %token <Region.t> Down        (* "down"       *)
 %token <Region.t> Fail        (* "fail"       *)
 %token <Region.t> If          (* "if"         *)
@@ -62,7 +63,7 @@
 %token <Region.t> Then        (* "then"       *)
 %token <Region.t> Else        (* "else"       *)
 %token <Region.t> Match       (* "match"      *)
-%token <Region.t> Null        (* "null"       *)
+%token <Region.t> Nothing     (* "nothing"    *)
 %token <Region.t> Procedure   (* "procedure"  *)
 %token <Region.t> Record      (* "record"     *)
 %token <Region.t> Step        (* "step"       *)
diff --git a/Parser.mly b/Parser.mly
index e7429c60a..fc9b471ee 100644
--- a/Parser.mly
+++ b/Parser.mly
@@ -149,11 +149,11 @@ core_type:
     in TypeApp {region; value = $1,$2}
   }
 | par(type_expr) {
-   ParType $1
+    ParType $1
   }
 
 type_tuple:
-  par(nsepseq(type_name,COMMA)) { $1 }
+  par(nsepseq(type_expr,COMMA)) { $1 }
 
 sum_type:
   nsepseq(variant,VBAR) {
@@ -369,6 +369,24 @@ const_decl:
 
 var_decl:
   Var var COLON type_expr ASS expr option(SEMI) {
+    let stop =
+      match $7 with
+        Some region -> region
+      |        None -> expr_to_region $6 in
+    let region = cover $1 stop in
+    let value = {
+      kwd_var    = $1;
+      name       = $2;
+      colon      = $3;
+      var_type   = $4;
+      assign     = $5;
+      init       = $6;
+      terminator = $7}
+    in {region; value}
+  }
+(*
+| Var var COLON type_name type_tuple
+  ASS extended_expr option(SEMI) {
     let stop =
       match $7 with
         Some region -> region
@@ -385,18 +403,23 @@ var_decl:
     in {region; value}
   }
 
+extended_expr:
+  expr              { }
+| LBRACKET RBRACKET { }
+| C_None            { }
+ *)
 instruction:
   single_instr { Single $1 }
 | block        { Block  $1 }
 
 single_instr:
-  conditional {     Cond $1 }
-| match_instr {    Match $1 }
-| ass         {      Ass $1 }
-| loop        {     Loop $1 }
-| proc_call   { ProcCall $1 }
-| Null        {     Null $1 }
-| fail_instr  {     Fail $1 }
+  conditional {      Cond $1 }
+| match_instr {     Match $1 }
+| assignment  {    Assign $1 }
+| loop        {      Loop $1 }
+| proc_call   {  ProcCall $1 }
+| fail_instr  {      Fail $1 }
+| Do Nothing  { let region = cover $1 $2 in DoNothing region }
 
 fail_instr:
   Fail expr {
@@ -446,20 +469,10 @@ case:
     in {region; value}
   }
 
-ass:
-  var_ass {
-    VarAss $1
-  }
-| map_selection ASS expr {
-    let region = cover $1.region (expr_to_region $3)
-    and value  = {lookup = $1; ass = $2; expr = $3}
-    in MapAss {region; value}
-  }
-
-var_ass:
+assignment:
   var ASS expr {
     let region = cover $1.region (expr_to_region $3)
-    and value  = {var = $1; ass = $2; expr = $3}
+    and value  = {var = $1; assign = $2; expr = $3}
     in {region; value}
   }
 
@@ -478,12 +491,12 @@ while_loop:
   }
 
 for_loop:
-  For var_ass Down? To expr option(step_clause) block {
+  For assignment Down? To expr option(step_clause) block {
     let region = cover $1 $7.region in
     let value =
       {
         kwd_for  = $1;
-        var_ass  = $2;
+        assign   = $2;
         down     = $3;
         kwd_to   = $4;
         bound    = $5;
@@ -521,7 +534,7 @@ expr:
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3} in
+    and value  = {arg1 = $1; op = $2; arg2 = $3} in
     LogicExpr (BoolExpr (Or {region; value}))
   }
 | conj_expr { $1 }
@@ -531,7 +544,7 @@ conj_expr:
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3} in
+    and value  = {arg1 = $1; op = $2; arg2 = $3} in
     LogicExpr (BoolExpr (And {region; value}))
   }
 | comp_expr { $1 }
@@ -541,42 +554,42 @@ comp_expr:
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3} in
+    and value  = {arg1 = $1; op = $2; arg2 = $3} in
     LogicExpr (CompExpr (Lt {region; value}))
   }
 | comp_expr LEQ cat_expr {
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in LogicExpr (CompExpr (Leq {region; value}))
   }
 | comp_expr GT cat_expr {
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in LogicExpr (CompExpr (Gt {region; value}))
   }
 | comp_expr GEQ cat_expr {
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in LogicExpr (CompExpr (Geq {region; value}))
   }
 | comp_expr EQUAL cat_expr {
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in LogicExpr (CompExpr (Equal {region; value}))
   }
 | comp_expr NEQ cat_expr {
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in LogicExpr (CompExpr (Neq {region; value}))
   }
 | cat_expr { $1 }
@@ -586,7 +599,7 @@ cat_expr:
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in StringExpr (Cat {region; value})
   }
 | cons_expr { $1 }
@@ -596,7 +609,7 @@ cons_expr:
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in ListExpr (Cons {region; value})
   }
 | add_expr { $1 }
@@ -606,14 +619,14 @@ add_expr:
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in ArithExpr (Add {region; value})
   }
 | add_expr MINUS mult_expr {
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in ArithExpr (Sub {region; value})
   }
 | mult_expr { $1 }
@@ -623,21 +636,21 @@ mult_expr:
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in ArithExpr (Mult {region; value})
   }
 | mult_expr SLASH unary_expr {
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in ArithExpr (Div {region; value})
   }
 | mult_expr Mod unary_expr {
     let start  = expr_to_region $1
     and stop   = expr_to_region $3 in
     let region = cover start stop
-    and value  = {op1 = $1; op = $2; op2 = $3}
+    and value  = {arg1 = $1; op = $2; arg2 = $3}
     in ArithExpr (Mod {region; value})
   }
 | unary_expr { $1 }
@@ -646,13 +659,13 @@ unary_expr:
   MINUS core_expr {
     let stop   = expr_to_region $2 in
     let region = cover $1 stop
-    and value  = {op = $1; op1 = $2}
+    and value  = {op = $1; arg = $2}
     in ArithExpr (Neg {region; value})
   }
 | Not core_expr {
     let stop   = expr_to_region $2 in
     let region = cover $1 stop
-    and value  = {op = $1; op1 = $2} in
+    and value  = {op = $1; arg = $2} in
     LogicExpr (BoolExpr (Not {region; value}))
   }
 | core_expr { $1 }
@@ -684,14 +697,20 @@ core_expr:
   }
 
 map_selection:
-  map_name DOT brackets(expr) {
-    let region = cover $1.region $3.region in
+  map_name brackets(expr) {
+    let region = cover $1.region $2.region in
     let value  = {
-      map_name = $1;
-      selector = $2;
-      index    = $3}
+      map_path = Map $1;
+      index    = $2}
     in {region; value}
   }
+| record_projection brackets(expr) {
+    let region = cover $1.region $2.region in
+    let value  = {
+      map_path = MapPath $1;
+      index    = $2}
+    in {region; value}
+ }
 
 record_expr:
   record_injection  { RecordInj  $1 }
@@ -744,12 +763,13 @@ field_assignment:
   }
 
 record_projection:
-  record_name DOT field_name {
-    let region = cover $1.region $3.region in
-    let value  = {
+  record_name DOT nsepseq(field_name,DOT) {
+    let stop   = nsepseq_to_region (fun x -> x.region) $3 in
+    let region = cover $1.region stop
+    and value  = {
       record_name = $1;
       selector    = $2;
-      field_name  = $3}
+      field_path  = $3}
     in {region; value}
   }
 
diff --git a/ParserMain.ml b/ParserMain.ml
index a2a54ec6b..563913469 100644
--- a/ParserMain.ml
+++ b/ParserMain.ml
@@ -1,4 +1,4 @@
-(* Driver for the parser of Ligo *)
+(* Driver for the parser of LIGO *)
 
 open! EvalOpt (* Reads the command-line options: Effectful! *)
 
@@ -99,12 +99,14 @@ let () =
       print_error ~offsets EvalOpt.mode error
   | Sys_error msg -> Utils.highlight msg
 
+                                    (*
 (* Temporary: force dune to build AST2.ml *)
 let () =
   let open AST2 in
   let _ = s_ast in
   ()
 
+    (*
 (* Temporary: force dune to build AST2.ml *)
 let () =
   if false then
@@ -112,3 +114,5 @@ let () =
     ()
   else
     ()
+     *)
+     *)
diff --git a/Tests/Crowdfunding.li b/Tests/crowdfunding.ligo
similarity index 53%
rename from Tests/Crowdfunding.li
rename to Tests/crowdfunding.ligo
index c07ad8c8b..b60caa704 100644
--- a/Tests/Crowdfunding.li
+++ b/Tests/crowdfunding.ligo
@@ -1,4 +1,4 @@
-type state =
+type state is
   record
     goal     : nat;
     deadline : timestamp;
@@ -6,61 +6,63 @@ type state =
     funded   : bool
   end
 
-entrypoint donate (storage store : state;
-                   const sender  : address;
-                   const amount  : mutez)
-  : storage * list (operation) is
-  var operations : list (operation) := []
+entrypoint contribute (storage store : state;
+                       const sender  : address;
+                       const amount  : mutez)
+  : state * list (operation) is
+  var operations : list (operation) := ([] : list (operation)) // TODO
   begin
     if now > store.deadline then
       fail "Deadline passed"
     else
-      if store.backers.[sender] = None then
-        store :=
-          copy store with
-            record
-              backers = map_add store.backers (sender, amount)
-            end
-      else null
+      match store.backers[sender] with
+        None ->
+          store :=
+            copy store with
+              record
+                backers = add_binding ((sender, amount), store.backers)
+              end
+      | _ -> do nothing
+      end
   end with (store, operations)
 
 entrypoint get_funds (storage store : state; const sender : address)
-  : storage * list (operation) is
-  var operations : list (operation) := []
+  : state * list (operation) is
+  var operations : list (operation) := ([] : list (operation)) // TODO
   begin
     if sender = owner then
       if now >= store.deadline then
         if balance >= store.goal then
           begin
-            store := copy store with record funded = true end;
+            store := copy store with record funded = True end;
             operations := [Transfer (owner, balance)]
           end
         else fail "Below target"
       else fail "Too soon"
-    else null
+    else do nothing
   end with (store, operations)
 
 entrypoint claim (storage store : state; const sender : address)
-  : storage * list (operation) is
-  var operations : list (operation) := [];
+  : state * list (operation) is
+  var operations : list (operation) := ([] : list (operation)) // TODO
   var amount : mutez := 0
   begin
     if now <= store.deadline then
       fail "Too soon"
     else
-      match store.backers.[sender] with
+      match store.backers[sender] with
         None ->
           fail "Not a backer"
-      | Some amount ->
+      | Some (amount) ->
           if balance >= store.goal || store.funded then
             fail "Cannot refund"
           else
             begin
-              amount := store.backers.[sender];
+              amount := store.backers[sender];
               store :=
                 copy store with
                   record
-                    backers = map_remove store.backers sender
+                    backers = remove_entry (sender, store.backers)
                   end;
               operations := [Transfer (sender, amount)]
             end