Unify lex_cast* and avoid string copies

We always use lex_cast either to string or from string, so I made that
explicit, and got rid of some string copies in the process.  There was
also stringify(), which was redundant to lex_cast<string>.

We also always used lex_cast_hex to string, so that's now hard-coded and
again eliminated a string copy.

For lex_cast_qstring<string>, there's no need to write the streamify the
input, so a specialization now operates directly on the input.

Hopefully this is a bit cleaner, and I do measure it to be a little
faster on scripts with many probes.

1 files changed, 2 insertions, 3 deletions

diff --git a/parse.cxx b/parse.cxx
index a2e2b656..bfd7600f 100644
--- a/parse.cxx
+++ b/parse.cxx
@@ -754,9 +754,8 @@ lexer::scan (bool wildcard)
                  idx <= session.args.size()); // prevent overflow
       if (idx == 0 ||
           idx-1 >= session.args.size())
-        throw parse_error ("command line argument index " + lex_cast<string>(idx)
-                           + " out of range [1-" + lex_cast<string>(session.args.size()) + "]", n);
-
+        throw parse_error ("command line argument index " + lex_cast(idx)
+                           + " out of range [1-" + lex_cast(session.args.size()) + "]", n);
       string arg = session.args[idx-1];
       if (c == '$') input_put (arg);
       else input_put (lex_cast_qstring (arg));