1 files changed, 178 insertions, 0 deletions
diff --git a/libbuild2/functions-integer.cxx b/libbuild2/functions-integer.cxx
new file mode 100644
index 0000000..ddfc250
--- /dev/null
+++ b/libbuild2/functions-integer.cxx
@@ -0,0 +1,178 @@
+// file      : libbuild2/functions-integer.cxx -*- C++ -*-
+// license   : MIT; see accompanying LICENSE file
+
+#include <libbuild2/function.hxx>
+#include <libbuild2/variable.hxx>
+
+using namespace std;
+
+namespace build2
+{
+  extern bool
+  functions_sort_flags (optional<names>); // functions-builtin.cxx
+
+  static const char hex_digits[] = "0123456789abcdef";
+
+  static string
+  to_string (uint64_t i, optional<value> base, optional<value> width)
+  {
+    uint64_t b (base ? convert<uint64_t> (move (*base)) : 10);
+    size_t w (width
+              ? static_cast<size_t> (convert<uint64_t> (move (*width)))
+              : 0);
+
+    // One day we can switch to C++17 std::to_chars().
+    //
+    string r;
+    switch (b)
+    {
+    case 10:
+      {
+        r = to_string (i);
+        if (w > r.size ())
+          r.insert (0, w - r.size (), '0');
+        break;
+      }
+    case 16:
+      {
+        r.reserve (18);
+        r += "0x";
+
+        for (size_t j (64); j != 0; )
+        {
+          j -= 4;
+          size_t d ((i >> j) & 0x0f);
+
+          // Omit leading zeros but watch out for the i==0 corner case.
+          //
+          if (d != 0 || r.size () != 2 || j == 0)
+            r += hex_digits[d];
+        }
+
+        if (w > r.size () - 2)
+          r.insert (2, w - (r.size () - 2), '0');
+
+        break;
+      }
+    default:
+      throw invalid_argument ("unsupported base");
+    }
+
+    return r;
+  }
+
+  void
+  integer_functions (function_map& m)
+  {
+    function_family f (m, "integer");
+
+    // $string(<int64>)
+    // $string(<uint64>[, <base>[, <width>]])
+    //
+    f["string"] += [](int64_t i) {return to_string (i);};
+
+    f["string"] += [](uint64_t i, optional<value> base, optional<value> width)
+    {
+      return to_string (i, move (base), move (width));
+    };
+
+    // $integer_sequence(<begin>, <end>[, <step>])
+    //
+    // Return the list of uint64 integers starting from <begin> (including) to
+    // <end> (excluding) with the specified <step> or 1 if unspecified. If
+    // <begin> is greater than <end>, empty list is returned.
+    //
+    // Note that currently negative numbers are not supported but this could
+    // be handled if required (e.g., by returning int64s in this case).
+    //
+    // Note also that we could improve this by adding a shortcut to get the
+    // indexes of a list (for example, $indexes(<list>) plus potentially a
+    // similar $keys() function for maps).
+    //
+    f["integer_sequence"] += [](value begin, value end, optional<value> step)
+    {
+      uint64_t b (convert<uint64_t> (move (begin)));
+      uint64_t e (convert<uint64_t> (move (end)));
+      uint64_t s (step ? convert<uint64_t> (move (*step)) : 1);
+
+      uint64s r;
+      if (b < e)
+      {
+        r.reserve (static_cast<size_t> ((e - b) / s + 1));
+
+        for (; b < e; b += s)
+          r.push_back (static_cast<size_t> (b));
+      }
+
+      return r;
+    };
+
+    // $size(<ints>)
+    //
+    // Return the number of elements in the sequence.
+    //
+    f["size"] += [] (int64s v) {return v.size ();};
+    f["size"] += [] (uint64s v) {return v.size ();};
+
+    // $sort(<ints> [, <flags>])
+    //
+    // Sort integers in ascending order.
+    //
+    // The following flags are supported:
+    //
+    //   dedup - in addition to sorting also remove duplicates
+    //
+    f["sort"] += [](int64s v, optional<names> fs)
+    {
+      sort (v.begin (), v.end ());
+
+      if (functions_sort_flags (move (fs)))
+        v.erase (unique (v.begin(), v.end()), v.end ());
+
+      return v;
+    };
+
+    f["sort"] += [](uint64s v, optional<names> fs)
+    {
+      sort (v.begin (), v.end ());
+
+      if (functions_sort_flags (move (fs)))
+        v.erase (unique (v.begin(), v.end()), v.end ());
+
+      return v;
+    };
+
+    // $find(<ints>, <int>)
+    //
+    // Return true if the integer sequence contains the specified integer.
+    //
+    f["find"] += [](int64s vs, value v)
+    {
+      return find (vs.begin (), vs.end (),
+                   convert<int64_t> (move (v))) != vs.end ();
+    };
+
+    f["find"] += [](uint64s vs, value v)
+    {
+      return find (vs.begin (), vs.end (),
+                   convert<uint64_t> (move (v))) != vs.end ();
+    };
+
+    // $find_index(<ints>, <int>)
+    //
+    // Return the index of the first element in the integer sequence that is
+    // equal to the specified integer or $size(<ints>) if none is found.
+    //
+    f["find_index"] += [](int64s vs, value v)
+    {
+      auto i (find (vs.begin (), vs.end (), convert<int64_t> (move (v))));
+      return i != vs.end () ? i - vs.begin () : vs.size ();
+    };
+
+    f["find_index"] += [](uint64s vs, value v)
+    {
+      auto i (find (vs.begin (), vs.end (), convert<uint64_t> (move (v))));
+      return i != vs.end () ? i - vs.begin () : vs.size ();
+    };
+  }
+}