FILE
  RsFunctionImpl(FUNCTION)
    PsiElement(fn)('fn')
    PsiWhiteSpace(' ')
    PsiElement(identifier)('main')
    RsValueParameterListImpl(VALUE_PARAMETER_LIST)
      PsiElement(()('(')
      PsiElement())(')')
    PsiWhiteSpace(' ')
    RsBlockImpl(BLOCK)
      PsiElement({)('{')
      PsiWhiteSpace('\n    ')
      RsExprStmtImpl(EXPR_STMT)
        RsBlockExprImpl(BLOCK_EXPR)
          RsBlockImpl(BLOCK)
            PsiElement({)('{')
            PsiElement(})('}')
      PsiWhiteSpace(' ')
      PsiComment(<EOL_COMMENT>)('// This should a stmt.')
      PsiWhiteSpace('\n    ')
      RsExprStmtImpl(EXPR_STMT)
        RsBlockExprImpl(BLOCK_EXPR)
          RsBlockImpl(BLOCK)
            PsiElement({)('{')
            PsiElement(})('}')
      PsiWhiteSpace(' ')
      PsiComment(<EOL_COMMENT>)('// And this one is an expr.')
      PsiWhiteSpace('\n')
      PsiElement(})('}')
