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diff --git a/ruby_1_9_3/lib/yaml/dbm.rb b/ruby_1_9_3/lib/yaml/dbm.rb
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+require 'yaml'
+require 'dbm'
+
+module YAML
+
+# YAML + DBM = YDBM
+#
+# YAML::DBM provides the same interface as ::DBM.
+#
+# However, while DBM only allows strings for both keys and values,
+# this library allows one to use most Ruby objects for values
+# by first converting them to YAML. Keys must be strings.
+#
+# Conversion to and from YAML is performed automatically.
+#
+# See the documentation for ::DBM and ::YAML for more information.
+class DBM < ::DBM
+ VERSION = "0.1"
+
+ # Return value associated with +key+ from database.
+ #
+ # Returns +nil+ if there is no such +key+.
+ def []( key )
+ fetch( key )
+ end
+
+ # :call-seq:
+ # []=( key, value )
+ #
+ # Set +key+ to +value+ in database.
+ #
+ # +value+ will be converted to YAML before storage.
+ def []=( key, val )
+ store( key, val )
+ end
+
+ # :call-seq:
+ # fetch( key, ifnone = nil )
+ # fetch( key, &block )
+ #
+ # Return value associated with +key+.
+ #
+ # If there is no value for +key+ and no block is given, returns +ifnone+.
+ #
+ # Otherwise, calls block passing in the given +key+.
+ def fetch( keystr, ifnone = nil )
+ begin
+ val = super( keystr )
+ return YAML.load( val ) if String === val
+ rescue IndexError
+ end
+ if block_given?
+ yield keystr
+ else
+ ifnone
+ end
+ end
+
+ # Deprecated, used YAML::DBM#key instead.
+ def index( keystr )
+ super( keystr.to_yaml )
+ end
+
+ # Returns an array containing the values associated with the given keys.
+ def values_at( *keys )
+ keys.collect { |k| fetch( k ) }
+ end
+
+ # Deletes value from database associated with +key+.
+ #
+ # Returns value or +nil+.
+ def delete( key )
+ v = super( key )
+ if String === v
+ v = YAML.load( v )
+ end
+ v
+ end
+
+ # Calls the given block once for each +key+, +value+ pair in the database.
+ # Deletes all entries for which the block returns true.
+ #
+ # Returns +self+.
+ def delete_if # :yields: [key, value]
+ del_keys = keys.dup
+ del_keys.delete_if { |k| yield( k, fetch( k ) ) == false }
+ del_keys.each { |k| delete( k ) }
+ self
+ end
+
+ # Converts the contents of the database to an in-memory Hash, then calls
+ # Hash#reject with the specified code block, returning a new Hash.
+ def reject
+ hsh = self.to_hash
+ hsh.reject { |k,v| yield k, v }
+ end
+
+ # Calls the given block once for each +key+, +value+ pair in the database.
+ #
+ # Returns +self+.
+ def each_pair # :yields: [key, value]
+ keys.each { |k| yield k, fetch( k ) }
+ self
+ end
+
+ # Calls the given block for each value in database.
+ #
+ # Returns +self+.
+ def each_value # :yields: value
+ super { |v| yield YAML.load( v ) }
+ self
+ end
+
+ # Returns an array of values from the database.
+ def values
+ super.collect { |v| YAML.load( v ) }
+ end
+
+ # Returns true if specified value is found in the database.
+ def has_value?( val )
+ each_value { |v| return true if v == val }
+ return false
+ end
+
+ # Returns a Hash (not a DBM database) created by using each value in the
+ # database as a key, with the corresponding key as its value.
+ #
+ # Note that all values in the hash will be Strings, but the keys will be
+ # actual objects.
+ def invert
+ h = {}
+ keys.each { |k| h[ self.fetch( k ) ] = k }
+ h
+ end
+
+ # Replaces the contents of the database with the contents of the specified
+ # object. Takes any object which implements the each_pair method, including
+ # Hash and DBM objects.
+ def replace( hsh )
+ clear
+ update( hsh )
+ end
+
+ # Removes a [key, value] pair from the database, and returns it.
+ # If the database is empty, returns +nil+.
+ #
+ # The order in which values are removed/returned is not guaranteed.
+ def shift
+ a = super
+ a[1] = YAML.load( a[1] ) if a
+ a
+ end
+
+ # :call-seq:
+ # select( &block )
+ # select( *keys )
+ #
+ # If a block is provided, returns a new array containing [key, value] pairs
+ # for which the block returns true.
+ #
+ # Otherwise, same as #values_at
+ def select( *keys )
+ if block_given?
+ self.keys.collect { |k| v = self[k]; [k, v] if yield k, v }.compact
+ else
+ values_at( *keys )
+ end
+ end
+
+ # :call-seq:
+ # store( key, value )
+ #
+ #Stores +value+ in database with +key+ as the index. +value+ is converted
+ #to YAML before being stored.
+ #
+ #Returns +value+
+ def store( key, val )
+ super( key, val.to_yaml )
+ val
+ end
+
+ # Updates the database with multiple values from the specified object.
+ # Takes any object which implements the each_pair method, including
+ # Hash and DBM objects.
+ #
+ # Returns +self+.
+ def update( hsh )
+ hsh.keys.each do |k|
+ self.store( k, hsh.fetch( k ) )
+ end
+ self
+ end
+
+ # Converts the contents of the database to an array of [key, value] arrays,
+ # and returns it.
+ def to_a
+ a = []
+ keys.each { |k| a.push [ k, self.fetch( k ) ] }
+ a
+ end
+
+
+ # Converts the contents of the database to an in-memory Hash object, and
+ # returns it.
+ def to_hash
+ h = {}
+ keys.each { |k| h[ k ] = self.fetch( k ) }
+ h
+ end
+
+ alias :each :each_pair
+end
+
+end