我们从Python开源项目中，提取了以下3个代码示例，用于说明如何使用pyparsing.CaselessKeyword()。
def grammar(): """Define the query grammar. Backus-Naur form (BNF) of the grammar:: <grammar> ::= <item> | <item> <boolean> <grammar> <item> ::= <hosts> | "(" <grammar> ")" <boolean> ::= "and not" | "and" | "xor" | "or" Given that the pyparsing library defines the grammar in a BNF-like style, for the details of the tokens not specified above check directly the source code. Returns: pyparsing.ParserElement: the grammar parser. """ # Boolean operators boolean = (pp.CaselessKeyword('and not').leaveWhitespace() | pp.CaselessKeyword('and') | pp.CaselessKeyword('xor') | pp.CaselessKeyword('or'))('bool') # Parentheses lpar = pp.Literal('(')('open_subgroup') rpar = pp.Literal(')')('close_subgroup') # Hosts selection: clustershell (,!&^[]) syntax is allowed: host10[10-42].domain hosts = (~(boolean) + pp.Word(pp.alphanums + '-_.,!&^[]'))('hosts') # Final grammar, see the docstring for its BNF based on the tokens defined above # Groups are used to split the parsed results for an easy access full_grammar = pp.Forward() item = hosts | lpar + full_grammar + rpar full_grammar << pp.Group(item) + pp.ZeroOrMore(pp.Group(boolean + item)) # pylint: disable=expression-not-assigned return full_grammar
def grammar(): """Define the query grammar. Backus-Naur form (BNF) of the grammar:: <grammar> ::= <item> | <item> <and_or> <grammar> <item> ::= [<neg>] <query-token> | [<neg>] "(" <grammar> ")" <query-token> ::= <token> | <hosts> <token> ::= <category>:<key> [<operator> <value>] Given that the pyparsing library defines the grammar in a BNF-like style, for the details of the tokens not specified above check directly the source code. Returns: pyparsing.ParserElement: the grammar parser. """ # Boolean operators and_or = (pp.CaselessKeyword('and') | pp.CaselessKeyword('or'))('bool') # 'neg' is used as label to allow the use of dot notation, 'not' is a reserved word in Python neg = pp.CaselessKeyword('not')('neg') operator = pp.oneOf(OPERATORS, caseless=True)('operator') # Comparison operators quoted_string = pp.quotedString.copy().addParseAction(pp.removeQuotes) # Both single and double quotes are allowed # Parentheses lpar = pp.Literal('(')('open_subgroup') rpar = pp.Literal(')')('close_subgroup') # Hosts selection: glob (*) and clustershell (,!&^[]) syntaxes are allowed: # i.e. host10[10-42].*.domain hosts = quoted_string | (~(and_or | neg) + pp.Word(pp.alphanums + '-_.*,!&^[]')) # Key-value token for allowed categories using the available comparison operators # i.e. F:key = value category = pp.oneOf(CATEGORIES, caseless=True)('category') key = pp.Word(pp.alphanums + '-_.%@:')('key') selector = pp.Combine(category + ':' + key) # i.e. F:key # All printables characters except the parentheses that are part of this or the global grammar all_but_par = ''.join([c for c in pp.printables if c not in ('(', ')', '{', '}')]) value = (quoted_string | pp.Word(all_but_par))('value') token = selector + pp.Optional(operator + value) # Final grammar, see the docstring for its BNF based on the tokens defined above # Groups are used to split the parsed results for an easy access full_grammar = pp.Forward() item = pp.Group(pp.Optional(neg) + (token | hosts('hosts'))) | pp.Group( pp.Optional(neg) + lpar + full_grammar + rpar) full_grammar << item + pp.ZeroOrMore(pp.Group(and_or) + full_grammar) # pylint: disable=expression-not-assigned return full_grammar
def grammar(backend_keys): """Define the main multi-query grammar. Cumin provides a user-friendly generic query language that allows to combine the results of subqueries for multiple backends: * Each query part can be composed with the others using boolean operators ``and``, ``or``, ``and not``, ``xor``. * Multiple query parts can be grouped together with parentheses ``(``, ``)``. * Specific backend query ``I{backend-specific query syntax}``, where ``I`` is an identifier for the specific backend. * Alias replacement, according to aliases defined in the configuration file ``A:group1``. * The identifier ``A`` is reserved for the aliases replacement and cannot be used to identify a backend. * A complex query example: ``(D{host1 or host2} and (P{R:Class = Role::MyClass} and not A:group1)) or D{host3}`` Backus-Naur form (BNF) of the grammar:: <grammar> ::= <item> | <item> <boolean> <grammar> <item> ::= <backend_query> | <alias> | "(" <grammar> ")" <backend_query> ::= <backend> "{" <query> "}" <alias> ::= A:<alias_name> <boolean> ::= "and not" | "and" | "xor" | "or" Given that the pyparsing library defines the grammar in a BNF-like style, for the details of the tokens not specified above check directly the source code. Arguments: backend_keys (list): list of the GRAMMAR_PREFIX for each registered backend. Returns: pyparsing.ParserElement: the grammar parser. """ # Boolean operators boolean = (pp.CaselessKeyword('and not').leaveWhitespace() | pp.CaselessKeyword('and') | pp.CaselessKeyword('xor') | pp.CaselessKeyword('or'))('bool') # Parentheses lpar = pp.Literal('(')('open_subgroup') rpar = pp.Literal(')')('close_subgroup') # Backend query: P{PuppetDB specific query} query_start = pp.Combine(pp.oneOf(backend_keys, caseless=True)('backend') + pp.Literal('{')) query_end = pp.Literal('}') # Allow the backend specific query to use the end_query token as well, as long as it's in a quoted string # and fail if there is a query_start token before the first query_end is reached query = pp.SkipTo(query_end, ignore=pp.quotedString, failOn=query_start)('query') backend_query = pp.Combine(query_start + query + query_end) # Alias alias = pp.Combine(pp.CaselessKeyword('A') + ':' + pp.Word(pp.alphanums + '-_.+')('alias')) # Final grammar, see the docstring for its BNF based on the tokens defined above # Group are used to have an easy dictionary access to the parsed results full_grammar = pp.Forward() item = backend_query | alias | lpar + full_grammar + rpar full_grammar << pp.Group(item) + pp.ZeroOrMore(pp.Group(boolean + item)) # pylint: disable=expression-not-assigned return full_grammar
