4 files changed, 24 insertions, 34 deletions
diff --git a/src/include/open-axiom/InputFragment b/src/include/open-axiom/InputFragment
index 63139db4..67863e44 100644
--- a/src/include/open-axiom/InputFragment
+++ b/src/include/open-axiom/InputFragment
@@ -36,6 +36,7 @@
 #ifndef OPENAXIOM_INPUTFRAGMENT_included
 #define OPENAXIOM_INPUTFRAGMENT_included
 
+#include <stdint.h>
 #include <vector>
 #include <string>
 #include <stack>
@@ -43,7 +44,7 @@
 namespace OpenAxiom {
    // Datatypes for locating lines and columns.
    using LineNumber = std::size_t;
-   using ColumnIndex = std::size_t;
+   using ColumnIndex = uint16_t;
 
    enum class LineKind : uint8_t {
       Ordinary,                 // Ordinary input line
@@ -65,9 +66,11 @@ namespace OpenAxiom {
    };
 
    // Cursor into a fragment.
+   // Note: We don't expect people to write large fragements
+   //       either in length or in width.
    struct FragmentCursor {
-      std::size_t line;         // index of a line in a fragment
-      std::size_t column;       // column number at line.
+      uint16_t line;            // index of a line in a fragment
+      uint16_t column;          // column number at line.
 
       inline FragmentCursor& operator++() {
          ++column;
@@ -92,6 +95,8 @@ namespace OpenAxiom {
       }
    };
 
+   std::ostream& operator<<(std::ostream&, FragmentCursor);
+
    // A program fragment is a logical line, composed of possibly
    // several physical lines subject to the off-side rule.  As a
    // special case, a line ending with the underbar character
diff --git a/src/include/open-axiom/token b/src/include/open-axiom/token
index f487cb3b..943d01cc 100644
--- a/src/include/open-axiom/token
+++ b/src/include/open-axiom/token
@@ -72,17 +72,10 @@ namespace OpenAxiom {
 
    std::ostream& operator<<(std::ostream&, TokenValue);
 
-   struct Locus {
-      LineNumber line;
-      ColumnIndex column;
-   };
-
-   std::ostream& operator<<(std::ostream&, const Locus&);
-
-   // Program text region
+   // Program text region, with a fragment.
    struct Region {
-      Locus start;
-      Locus end;
+      FragmentCursor start;
+      FragmentCursor end;
    };
 
    // Given a symbolic or alphabetic token, retrieve its category
@@ -99,9 +92,7 @@ namespace OpenAxiom {
    TokenClassification classify(const std::string&);
 
    // Token data structure: a region of text with a classification.
-   struct Token : Region, TokenClassification {
-      using Location = Locus;
-   };
+   struct Token : Region, TokenClassification { };
 
    // -- Exception types
    struct EndOfStringUnseen {
@@ -180,9 +171,9 @@ namespace OpenAxiom {
    }
 
    template<typename T>
-   inline T& ws_token(T& t, const Locus& loc) {
+   inline T& ws_token(T& t, FragmentCursor pos) {
       t.category = TokenCategory::Whitespace;
-      t.end = loc;
+      t.end = pos;
       return t;
    }
 
@@ -571,26 +562,20 @@ namespace OpenAxiom {
          break;
       }
 
-      t.end = { frag(pos).number, pos.column };
+      t.end = pos;
       return t;
    }
 
-   inline Locus location(const Fragment& frag, const FragmentCursor& pos) {
-      if (pos.line < frag.size())
-         return { frag[pos.line].number, pos.column };
-      return { frag.back().number + 1, { } };
-   }
-
    template<typename Tok>
    Tok Tokenizer<Tok>::get(Language dialect) {
       Tok t { };
-      t.start = location(frag, pos);
+      t.start = pos;
       
       if (eos())
          return eos_token(t);
       else if (isblank(frag[pos])) {
          skip_whitespace(frag(pos), pos.column);
-         return ws_token(t, location(frag, pos));
+         return ws_token(t, pos);
       }
       else if (line_continuation()) {
          if (next_line(frag, pos))
@@ -600,7 +585,7 @@ namespace OpenAxiom {
       else if (pos.column >= line_length()) {
          if (not next_line(frag, pos))
             return eos_token(t);
-         t.start = t.end = location(frag, pos);
+         t.start = t.end = pos;
          auto indent = indents.top();
          if (indent.column < pos.column) {
             indents.push(pos);
diff --git a/src/io/InputFragment.cxx b/src/io/InputFragment.cxx
index 01970f84..595b88b1 100644
--- a/src/io/InputFragment.cxx
+++ b/src/io/InputFragment.cxx
@@ -41,6 +41,11 @@
 #include <open-axiom/SourceInput>
 
 namespace OpenAxiom {
+
+   std::ostream& operator<<(std::ostream& os, FragmentCursor cur) {
+      return os << '{' << cur.line << '-' << cur.column << '}';
+   }
+   
    // Formatting program fragments.
    std::ostream& operator<<(std::ostream& os, const Fragment& f) {
       std::copy(f.begin(), f.end(),
diff --git a/src/syntax/token.cxx b/src/syntax/token.cxx
index 011520a8..e1c02e3f 100644
--- a/src/syntax/token.cxx
+++ b/src/syntax/token.cxx
@@ -35,12 +35,7 @@
 #include <iostream>
 
 namespace OpenAxiom {
-   std::ostream& operator<<(std::ostream& os, const Locus& l) {
-      return os << '{' << l.line << ", " << l.column << '}';
-   }
-
-   std::ostream&
-   operator<<(std::ostream& os, TokenCategory tc) {
+   std::ostream& operator<<(std::ostream& os, TokenCategory tc) {
       switch (tc) {
       case TokenCategory::Unclassified: os << "UNCLASSIFIED"; break;
       case TokenCategory::Whitespace: os << "WHITESPACE"; break;