language.py 文件源码

def _create_block_bnf():
    global block_bnf, time_interval, slot_id, statement, block_id, ident, stream

    if block_bnf is not None:
        return

    trigger_clause = Group(stream_trigger | Group(stream).setResultsName('stream_always') | Group(ident).setResultsName('identifier'))

    every_block_id = Group(Literal(u'every').suppress() - time_interval).setResultsName('every_block')
    when_block_id = Group(Literal(u'when').suppress() + Literal("connected").suppress() - Literal("to").suppress() - slot_id).setResultsName('when_block')
    latch_block_id = Group(Literal(u'when').suppress() - stream_trigger).setResultsName('latch_block')
    config_block_id = Group(Literal(u'config').suppress() - slot_id).setResultsName('config_block')
    on_block_id = Group(Literal(u'on').suppress() - trigger_clause.setResultsName('triggerA') - Optional((Literal("and") | Literal("or")) - trigger_clause.setResultsName('triggerB'))).setResultsName('on_block')

    block_id = every_block_id | when_block_id | latch_block_id | config_block_id | on_block_id

    block_bnf = Forward()
    statement = generic_statement | block_bnf

    block_bnf << Group(block_id + Group(Literal(u'{').suppress() + ZeroOrMore(statement) + Literal(u'}').suppress())).setResultsName('block')