grande.rb in rio-0.3.9

- old
+ new

@@ -1,8 +1,8 @@
 #--
 # =============================================================================== 
-# Copyright (c) 2005, 2006 Christopher Kleckner
+# Copyright (c) 2005,2006,2007 Christopher Kleckner
 # All rights reserved
 #
 # This file is part of the Rio library for ruby.
 #
 # Rio is free software; you can redistribute it and/or modify
@@ -21,37 +21,57 @@
 # =============================================================================== 
 #++
 #
 # To create the documentation for Rio run the command
 #  ruby build_doc.rb
-# from the distribution directory. Then point your browser at the 'doc/rdoc' directory.
+# from the distribution directory.
 #
 # Suggested Reading
 # * RIO::Doc::SYNOPSIS
 # * RIO::Doc::INTRO
 # * RIO::Doc::HOWTO
+# * RIO::Doc::EXAMPLES
 # * RIO::Rio
 #
-# <b>Rio is pre-alpha software. 
-# The documented interface and behavior is subject to change without notice.</b>
 
 
 require 'rio/match'
 module RIO
   module Grande #:nodoc: all
     include Match::Common
     def [](*args)
       #p "#{callstr('[]',*args)} ss_type=#{cx['ss_type']} stream_iter=#{stream_iter?}"
       ss_args = cx['ss_args'] = args
+      rtn = nil
       if ss_args and (ss_type = ss_type?(_ss_keys()))
-        return self.__send__(ss_type,*(ss_args)).to_a
+        rtn = self.__send__(ss_type,*(ss_args)).to_a
       else
-        return to_a()
+        rtn = to_a()
       end
+      _ss_returns_first? ? _ss_return_first(rtn) : rtn
     end
 
+    private
+
+    def _ss_return_first(ary)
+      _ss_clear_single_return()
+      ary[0] 
+    end
+
+    SINGLE_RETURN_KEYS = %[line record row]
+
+    def _ss_clear_single_return
+      SINGLE_RETURN_KEYS.each do |key|
+        cx.delete(key)
+      end
+    end
+
+    def _ss_returns_first?
+      cx['line'] || cx['record'] || cx['row']
+    end
+
     def fixnumss(*args)
-      #p "#{callstr('[]',*args)} ss_type=#{cx['ss_type']} stream_iter=#{stream_iter?}"
+
       #p args[0].class,ss_type?(_ss_keys())
       ss_args = cx['ss_args'] = args
       if ss_args.length == 1 and ss_args[0].kind_of?(Fixnum) and !cx.has_key?('dirlines')
         ans = nil
         ss_type = ss_type?(_ss_keys())