使用Python和pyparsing解析Visual Basic函数的参数列表
我正在尝试使用解析Visual Basic(VBA)函数声明,以便将它们转换为Python语法 通常的VBA函数头不是一个大问题,这对我来说很好。但我对论点列表有困难:使用Python和pyparsing解析Visual Basic函数的参数列表,python,vba,pyparsing,Python,Vba,Pyparsing,我正在尝试使用解析Visual Basic(VBA)函数声明,以便将它们转换为Python语法 通常的VBA函数头不是一个大问题,这对我来说很好。但我对论点列表有困难: Public Function MyFuncName(first As Integer, Second As String) As Integer 参数由一个逗号分隔的列表组成,列表中有0到多个部分,如: VarName VarName As VarType Optional VarName As VarType = Init
Public Function MyFuncName(first As Integer, Second As String) As Integer
参数由一个逗号分隔的列表组成,列表中有0到多个部分,如:
VarName
VarName As VarType
Optional VarName As VarType = InitValue
ByVal VarName As VarType
其中“Optional”、“ByVal”和“ByRef”以及类型声明都是完全可选的
我的想法是通过
allparams = Regex('[^)]*').setResultsName('params')
然后分别解析它们。这与单个参数匹配:
variablename = Word(alphas + '_', alphanums + '_')
typename = variablename.setResultsName('type')
default_value = Word(alphanums)
optional_term = oneOf('Optional', True)
byval_term = oneOf('ByRef ByVal', True)
paramsparser = Optional(optional_term) \
+Optional(byval_term) \
+variablename.setResultsName('pname', True) \
+Optional('As' + typename) \
+Optional('=' + default_value)
但是即使使用delimitedList(paramsparser)
我也只能得到第一个
AssertionError: 'def test(one):\n\tpass' != 'def test(one, two):\n\tpass'
- def test(one):
+ def test(one, two):
? +++++
你有什么想法吗?我使用了你发布的代码,并将其包装在一个
分隔列表中,得到了两个参数:
paramsparser = Optional(optional_term) \
+Optional(byval_term) \
+variablename.setResultsName('pname', True) \
+Optional('As' + typename) \
+Optional('=' + default_value)
parser = "(" + delimitedList(paramsparser) + ")"
parser.runTests("""\
(one, two)
(ByRef one As Int = 1, Optional ByVal two As Char)
""")
印刷品:
(one, two)
['(', 'one', 'two', ')']
- pname: ['one', 'two']
(ByRef one As Int = 1, Optional ByVal two As Char)
['(', 'ByRef', 'one', 'As', 'Int', '=', '1', 'Optional', 'ByVal', 'two', 'As', 'Char', ')']
- pname: ['one', 'two']
- type: 'Char'
但由于每个参数有这么多字段,我建议为每个字段指定一个单独的结果名称,并在组中换行,以防止参数相互重叠。下面是我对解析器的修改(非常有帮助,您发布了不同可选声明字段的各种表单):
然后,我不再使用正则表达式获取参数,然后在单独的步骤中重新解析,而是将其包含在整个函数表达式定义中:
protection = oneOf("Public Private", asKeyword=True)
func_expr = (
protection("protection")
+ FUNCTION
+ identifier("fname")
+ Group(LPAR + delimitedList(param_expr) + RPAR)("parameters")
+ Optional(AS + type_expr("return_type"))
)
tests = """
Public Function MyFuncName(first As Integer, Second As String) As Integer
"""
func_expr.runTests(tests)
印刷品:
Public Function MyFuncName(first As Integer, Second As String) As Integer
['Public', 'Function', 'MyFuncName', [['first', 'As', 'Integer'], ['Second', 'As', 'String']], 'As', 'Integer']
- fname: 'MyFuncName'
- parameters: [['first', 'As', 'Integer'], ['Second', 'As', 'String']]
[0]:
['first', 'As', 'Integer']
- pname: 'first'
- ptype: 'Integer'
[1]:
['Second', 'As', 'String']
- pname: 'Second'
- ptype: 'String'
- protection: 'Public'
- return_type: 'Integer'
ViperMonkey是pyparsing中的VBA解析器,你可能会从中得到一些想法。非常感谢,@PaulMcG,这非常有帮助,我学到了更多关于pyparsing的知识!我刚刚在param_expr中添加了一个Optional()
,因此整个参数字符串都是可选的。我添加了Sub
关键字,这是在VBA中没有结果的函数。
Public Function MyFuncName(first As Integer, Second As String) As Integer
['Public', 'Function', 'MyFuncName', [['first', 'As', 'Integer'], ['Second', 'As', 'String']], 'As', 'Integer']
- fname: 'MyFuncName'
- parameters: [['first', 'As', 'Integer'], ['Second', 'As', 'String']]
[0]:
['first', 'As', 'Integer']
- pname: 'first'
- ptype: 'Integer'
[1]:
['Second', 'As', 'String']
- pname: 'Second'
- ptype: 'String'
- protection: 'Public'
- return_type: 'Integer'