Groovy DSL == thermonuclear way of writing XML

The code:

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import groovy.xml.MarkupBuilder String createEAD(Closure closure) { def writer = new StringWriter() def xml = new MarkupBuilder(writer) xml.mkp.xmlDeclaration(version: '1.0', encoding: 'UTF-8') xml.'ead:ead'('xmlns:ead': 'urn:isbn:1-931666-22-9') { closure.delegate = new Object() { def text(Map attrs, content) { def a = attrs.keySet().find { it in ['bold', 'italic', 'underline'] } if(a && attrs[a]) { xml.'ead:emph' render: a, { text attrs.findAll({ it.key != a }), content } } else text content } def text(content) { if(content instanceof String) xml.mkp.yield content else if(content instanceof Closure) content() } } closure() } return writer.toString() } println createEAD { text bold: true, italic: true, { text 'Hello, ' text underline: true, 'world!' } }

produces XML:

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<?xml version='1.0' encoding='UTF-8'?> <ead:ead xmlns:ead='urn:isbn:1-931666-22-9'> <ead:emph render='bold'> <ead:emph render='italic'>Hello, <ead:emph render='underline'>world!</ead:emph> </ead:emph> </ead:emph> </ead:ead>