Class DBI::ColumnInfo
In: lib/dbi/columninfo.rb
Parent: DelegateClass(Hash)

This represents metadata for columns within a given table, such as the data type, whether or not the the column is a primary key, etc.

ColumnInfo is a delegate of Hash, but represents its keys indifferently, coercing all strings to symbols. It also has ostruct-like features, f.e.:

  h = ColumnInfo.new({ "foo" => "bar" })
  h[:foo] => "bar"
  h["foo"] => "bar"
  h.foo => "bar"

All of these forms have assignment forms as well.

Methods

[]   []=   default   method_missing   new  

Included Modules

Deprecated

Public Class methods

Create a new ColumnInfo object.

If no Hash is provided, one will be created for you. The hash will be shallow cloned for storage inside the object, and an attempt will be made to convert all string keys to symbols.

In the event that both string and symbol keys are provided in the initial hash, we cannot safely route around collisions and therefore a TypeError is raised.

[Source]

# File lib/dbi/columninfo.rb, line 31
        def initialize(hash=nil)
            @hash = hash.dup rescue nil
            @hash ||= Hash.new

            # coerce all strings to symbols
            @hash.keys.each do |x|
                if x.kind_of? String
                    sym = x.to_sym
                    if @hash.has_key? sym
                        raise ::TypeError, 
                            "#{self.class.name} may construct from a hash keyed with strings or symbols, but not both" 
                    end
                    @hash[sym] = @hash[x]
                    @hash.delete(x)
                end
            end

            super(@hash)
        end

Public Instance methods

[Source]

# File lib/dbi/columninfo.rb, line 51
        def [](key)
            @hash[key.to_sym]
        end

[Source]

# File lib/dbi/columninfo.rb, line 55
        def []=(key, value)
            @hash[key.to_sym] = value
        end

[Source]

# File lib/dbi/columninfo.rb, line 59
        def default() # :nodoc; XXX hack to get around Hash#default
            method_missing(:default)
        end

[Source]

# File lib/dbi/columninfo.rb, line 63
        def method_missing(sym, value=nil)
            if sym.to_s =~ /=$/
                sym = sym.to_s.sub(/=$/, '').to_sym
                @hash[sym] = value
            elsif sym.to_s =~ /\?$/
                sym = sym.to_s.sub(/\?$/, '').to_sym
                @hash[sym]
            else
                @hash[sym]
            end
        end

[Validate]