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/*!
    \contentspage list-of-items.html
    \page transformer-item.html
    \previouspage subproject-item.html
    \nextpage xpcservice-item.html
    \ingroup list-of-items

    \title Transformer Item
    \brief Creates files, typically from other files.

    A \e transformer takes zero or more inputs and produces one or more output artifacts
    from them. The following transformer creates one output file from one input file:
    \code
    Transformer {
        inputs: "raw_input.txt"
        Artifact {
            filePath: "processed_input.txt"
            fileTags: "processed_file"
        }
        prepare: {
            var cmd = new JavaScriptCommand();
            cmd.description = "Processing '" + input.filePath + "'";
            cmd.highlight = "codegen";
            cmd.sourceCode = function() {
                var file = new TextFile(input.filePath);
                var content = file.readAll();
                file.close()
                content = content.replace(/\r\n/g, "\n");
                file = new TextFile(output.filePath, TextFile.WriteOnly);
                file.truncate();
                file.write(content);
                file.close();
            }
            return cmd;
        }
    }
    \endcode
    This example exhibits some interesting features of transformers:
    \list
        \li If there is only one input file, the property \c input is available as syntactic sugar
            for \c inputs[0].
        \li The filenames of the output artifacts are available as \c outputs. If there is only one
            of these, it can be referred to it as \c output.
    \endlist

    A \c Transformer is always attached to a \c Product, possibly indirectly via a \c Module.

    \section1 Transformer Properties

    \table
    \header
        \li Property
        \li Type
        \li Default
        \li Description
    \row
        \li inputs
        \li stringList
        \li empty list
        \li The list of inputs to the transformer.
    \row
        \li prepare
        \li list of Javascript commands
        \li empty list
        \li The commands that the transformer runs. These typically read from the input files and
            write to the output files in some way.
    \row
        \li condition
        \li bool
        \li true
        \li If true, the transformer is enabled, otherwise it does nothing.
    \row
        \li explicitlyDependsOn
        \li stringList
        \li \c{undefined}
        \li A list of file tags. All output artifacts of this transformer will have a dependency
            to all artifacts with the given file tags.
    \row
        \li alwaysRun
        \li bool
        \li false
        \li If true, the transformer's commands are always executed, even if all output artifacts
            are up to date.
    \endtable

*/
