     let assign = skip >>> str("=") >>> skip
     let functionBody = expression.tag("body") >>> skip
     let ifKeyword = space >>> str("IF") >>> space
-    let `guard` = (ifKeyword >>> expression).maybe.tag("guard")
-    let function = functionSubject >>> dot >>> functionName >>> functionParameters.maybe >>> `guard` >>> assign >>> functionBody
+    let guardClause = (ifKeyword >>> expression).maybe.tag("guard")
+    let function = functionSubject >>> dot >>> functionName >>> functionParameters.maybe >>> guardClause >>> assign >>> functionBody
 
     // Lambdas.
 

    let statement = classDeclaration >>> `import` >>> function >>> expression
    let program = skip >>> statement

    return function
}

//    let listPattern = (list | listTemplate).tag("listPattern")


    // Functions.

    let parameter = pattern
    let functionSubject = parameter.tag("defunSubject")
    let functionName = name.tag("FUNC")
