13 lines
382 B
Python
13 lines
382 B
Python
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""" View validation code (using assertions, not the RNG schema). """
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def valid_page_in_book(arch):
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"""A `page` node must be below a `book` node."""
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return not arch.xpath('//page[not(ancestor::notebook)]')
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def valid_view(arch):
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if arch.tag == 'form':
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for pred in [valid_page_in_book]:
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if not pred(arch):
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return False
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return True
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