Package lepl :: Package lexer :: Module operators
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Source Code for Module lepl.lexer.operators

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29   
30  ''' 
31  Operators for tokens. 
32  ''' 
33   
34   
35  from lepl.support.context import Namespace 
36  from lepl.matchers.operators import ADD, AND, OR, APPLY, APPLY_RAW, NOT, \ 
37      KARGS, RAISE, REPEAT, FIRST, MAP, RepeatWrapper, REDUCE 
38  from lepl.matchers.derived import Add, Apply, Drop, KApply, Map 
39  from lepl.matchers.combine import And, Or, First 
40  from lepl.matchers.error import raise_error 
41   
42   
43  TOKENS = 'tokens' 
44  ''' 
45  This names a per-thread storage area that contains the definitions of  
46  operators (so tokens can have different operators to non-tokens).  All 
47  token matchers should reference this (either directly via `NamespaceMixin` 
48  or indirectly via `BaseToken`). 
49  ''' 
50   
51   
52 -class TokenNamespace(Namespace):
53 ''' 54 A modified version of the usual ``OperatorNamespace`` without handling of 55 spaces (since that is handled by the lexer), allowing Tokens and other 56 matchers to be configured separately (because they process different 57 types). 58 59 At one point this also defined alphabet and discard, used by the rewriter, 60 but because those are global values it makes more sense to supply them 61 directly to the rewriter. 62 ''' 63
64 - def __init__(self):
65 super(TokenNamespace, self).__init__({ 66 ADD: lambda a, b: Add(And(a, b)), 67 AND: And, 68 OR: Or, 69 APPLY: Apply, 70 APPLY_RAW: lambda a, b: Apply(a, b, raw=True), 71 NOT: Drop, 72 KARGS: KApply, 73 RAISE: lambda a, b: KApply(a, raise_error(b)), 74 REPEAT: RepeatWrapper, 75 FIRST: First, 76 MAP: Map, 77 REDUCE: None, 78 })
79