Permitted alphabet constraint¶
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class
pyasn1.type.constraint.
PermittedAlphabetConstraint
(*alphabet)¶ Create a PermittedAlphabetConstraint object.
The PermittedAlphabetConstraint satisfies any character string for as long as all its characters are present in the set of permitted characters.
The PermittedAlphabetConstraint object can only be applied to the character ASN.1 types such as
IA5String
.Parameters: *alphabet ( str
) – Full set of characters permitted by this constraint object.Examples
class BooleanValue(IA5String): ''' ASN.1 specification: BooleanValue ::= IA5String (FROM ('T' | 'F')) ''' subtypeSpec = PermittedAlphabetConstraint('T', 'F') # this will succeed truth = BooleanValue('T') truth = BooleanValue('TF') # this will raise ValueConstraintError garbage = BooleanValue('TAF')