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Type Description Component

As Esperanto is constructed to be a rather simple language to learn and use, there may be various technical terms which are not part of Esperanto, but none-the-less need to be used for communication in the course of international widget trade. For, example their might not be a word for ``amortize'' in Esperanto, but their might be words for ``paying ,'' ``gradual,'' ``of,'' ``off,'' and ``debts.'' One could then define the new term ``amortize'' by saying it is the ``gradual paying off of debts.'' All one would need to do this in Esperanto would be some construct which would be interpreted as a definition. A simple choice might be something like ``amortize = gradual paying off of debts.''

The Type Description Component plays this role for a WSDL document. It allows one, within a WSDL document, to define new communication primitives, or types, using known types. Just as you can build the definition of amortize out of the primitives ``paying ,'' ``gradual,'' ``of,'' ``off,'' and ``debts,'' so the WSDL Type Description Component allows you to build the a complicated type out of simple, well-known types. To give a flavor of how this occurs in WSDL lets take a peek at a WSDL document snippet: 

<types>
  <schema targetNamespace="http://example.com/stockquote.xsd" 
     xmlns="http://www.w3.org/2000/10/XMLSchema">
    <element name="TradePriceRequest">
      <complexType>
        <all>
          <element name="tickerSymbol" type="string"/>
        </all>
      </complexType>
    </element>
    <element name="TradePrice">
      <complexType>
        <all>
          <element name="price" type="float"/>
        </all>
      </complexType>
    </element>
  </schema>
</types>

This snippet defines two new types TradePriceRequest and TradePrice. The type TradePriceRequest is built of a single primitive type string that represents a string of characters. The type TradePrice is built also of a single primitive type float that represents a floating point number.

next up previous contents
Next: Message Description Component Up: WSDL Previous: WSDL   Contents
Andre Merzky 2004-05-13