From 85667336a18ea1a03bdb2d4071bcd93edc07094f Mon Sep 17 00:00:00 2001
From: Houtan Bastani <houtan@dynare.org>
Date: Mon, 12 Aug 2013 17:24:47 -0400
Subject: [PATCH] macroprocessor: add length command. closes #436

---
 doc/dynare.texi                  |  5 +++++
 preprocessor/macro/MacroBison.yy |  6 ++++--
 preprocessor/macro/MacroFlex.ll  |  3 ++-
 preprocessor/macro/MacroValue.cc |  8 +++++++-
 preprocessor/macro/MacroValue.hh | 13 ++++++++++++-
 5 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/doc/dynare.texi b/doc/dynare.texi
index ed04c7bc8..ea02204c9 100644
--- a/doc/dynare.texi
+++ b/doc/dynare.texi
@@ -7219,6 +7219,11 @@ extraction of sub-arrays: @i{e.g.} @code{@var{v}[4:6]}
 @item
 testing membership of an array: @code{in} operator (for example:
 @code{"b" in ["a", "b", "c"]} returns @code{1})
+@item
+getting the length of an array: @code{length} operator (for example:
+@code{length(["a", "b", "c"])} returns @code{3} and, hence,
+@code{1:length(["a", "b", "c"])} is equivalent to integer array
+@code{[1,2,3]})
 @end itemize
 
 Macro-expressions can be used at two places:
diff --git a/preprocessor/macro/MacroBison.yy b/preprocessor/macro/MacroBison.yy
index a7dc4fc5c..a7a6456e8 100644
--- a/preprocessor/macro/MacroBison.yy
+++ b/preprocessor/macro/MacroBison.yy
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008-2012 Dynare Team
+ * Copyright (C) 2008-2013 Dynare Team
  *
  * This file is part of Dynare.
  *
@@ -80,7 +80,7 @@ class MacroDriver;
 %}
 
 %token DEFINE LINE FOR IN IF ELSE ENDIF ECHO_DIR ERROR IFDEF IFNDEF
-%token LPAREN RPAREN LBRACKET RBRACKET EQUAL EOL
+%token LPAREN RPAREN LBRACKET RBRACKET EQUAL EOL LENGTH
 
 %token <int_val> INTEGER
 %token <string_val> NAME STRING
@@ -145,6 +145,8 @@ expr : INTEGER
            }
          delete $1;
        }
+     | LENGTH LPAREN array_expr RPAREN
+       { TYPERR_CATCH($$ = $3->length(), @$); }
      | LPAREN expr RPAREN
        { $$ = $2; }
      | expr PLUS expr
diff --git a/preprocessor/macro/MacroFlex.ll b/preprocessor/macro/MacroFlex.ll
index 7e3e5dbae..05a60329c 100644
--- a/preprocessor/macro/MacroFlex.ll
+++ b/preprocessor/macro/MacroFlex.ll
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008-2012 Dynare Team
+ * Copyright (C) 2008-2013 Dynare Team
  *
  * This file is part of Dynare.
  *
@@ -151,6 +151,7 @@ CONT \\\\
 <STMT,EXPR>[*]              { return token::TIMES; }
 <STMT,EXPR>[/]              { return token::DIVIDE; }
 <STMT,EXPR>in               { return token::IN; }
+<STMT,EXPR>length           { return token::LENGTH; }
 
 <STMT,EXPR>\"[^\"]*\"       {
                               yylval->string_val = new string(yytext + 1);
diff --git a/preprocessor/macro/MacroValue.cc b/preprocessor/macro/MacroValue.cc
index 646f6d8a1..65b3fc39d 100644
--- a/preprocessor/macro/MacroValue.cc
+++ b/preprocessor/macro/MacroValue.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008-2011 Dynare Team
+ * Copyright (C) 2008-2013 Dynare Team
  *
  * This file is part of Dynare.
  *
@@ -106,6 +106,12 @@ MacroValue::operator[](const MacroValue &mv) const throw (TypeError, OutOfBounds
   throw TypeError("Operator [] does not exist for this type");
 }
 
+const MacroValue *
+MacroValue::length() const throw (TypeError)
+{
+  throw TypeError("Length not supported for this type");
+}
+
 const MacroValue *
 MacroValue::append(const MacroValue *mv) const throw (TypeError)
 {
diff --git a/preprocessor/macro/MacroValue.hh b/preprocessor/macro/MacroValue.hh
index 0704b555f..d79c024c5 100644
--- a/preprocessor/macro/MacroValue.hh
+++ b/preprocessor/macro/MacroValue.hh
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008-2010 Dynare Team
+ * Copyright (C) 2008-2013 Dynare Team
  *
  * This file is part of Dynare.
  *
@@ -92,6 +92,8 @@ public:
   virtual string toString() const = 0;
   //! Converts value to array form
   virtual const MacroValue *toArray() const = 0;
+  //! Gets length
+  virtual const MacroValue *length() const throw (TypeError);
   //! Appends value at the end of an array
   /*! The argument must be an array. */
   virtual const MacroValue *append(const MacroValue *array) const throw (TypeError);
@@ -217,6 +219,8 @@ public:
   virtual string toString() const;
   //! Returns itself
   virtual const MacroValue *toArray() const;
+  //! Gets length
+  virtual const MacroValue *length() const throw (TypeError);
 };
 
 template<typename T>
@@ -329,4 +333,11 @@ ArrayMV<T>::toArray() const
   return this;
 }
 
+template<typename T>
+const MacroValue *
+ArrayMV<T>::length() const throw (TypeError)
+{
+  return new IntMV(driver, values.size());
+}
+
 #endif