== Introduction ==

This the fourth and last part of this recipe provides a few state machines for use with the validator.


== North American Telephone Number State Machine ==

{{{
#!python
from StateMachine import EBadCharacter, StateMachine

def areacode ( self, token ) :
    
    needClosingParen = False
    if token == '(' :
        needClosingParen = True
        token = self . nextToken ( )
    else :
        self . allTokens . insert ( 0, '(' )
    for c in range ( 3 ) :
        if not token . isdigit ( ) : raise EBadCharacter ( ) 
        token = self . nextToken ( )
    if needClosingParen :
        if token == ')' : 
            token = self . nextToken ( )
        else : raise EBadCharacter ( ) 
    else : 
        self . allTokens . insert ( len ( self . allTokens ) - 1,  ')' )
    if token == ' ' : token = self . nextToken ( )
    else :
        self . allTokens . insert ( len ( self . allTokens ) - 1,  ' ' )
    return 'exchange', token
    
def exchange ( self, token ) :
    
    for c in range ( 3 ) :
        if not token . isdigit ( ) : raise EBadCharacter ( ) 
        token = self . nextToken ( )
    if token == '-' : token = self . nextToken ( )
    elif token == ' ' : 
        token = self . nextToken ( )
        self . allTokens [ len ( self . allTokens ) - 2 ] = '-' 
    else :
        self . allTokens . insert ( len ( self . allTokens ) - 1,  '-' )
    return 'local', token
    
def local ( self, token ) :
    
    for c in range ( 4 ) :
        if not token . isdigit ( ) : raise EBadCharacter ( ) 
        if c < 3 : token = self . nextToken ( )
    return 'complete', None
    
def complete ( self, token ) : pass
    
statemachine = StateMachine ( )
statemachine . addState ( areacode )
statemachine . addState ( exchange )
statemachine . addState ( local )
statemachine . addState ( complete, True )
statemachine . setStartState ( areacode )
}}}

== Canadian Postal Code State Machine ==

{{{
#!python
from StateMachine import EBadCharacter, StateMachine
    
def local ( self, token ) :
    
    if not token . isalpha ( ) : raise EBadCharacter ( ) 
    token = self . nextToken ( )
    if not token . isdigit ( ) : raise EBadCharacter ( ) 
    token = self . nextToken ( )
    if not token . isalpha ( ) : raise EBadCharacter ( ) 
    token = self . nextToken ( )
            
    if token == ' ' : token = self . nextToken ( )
            
    if not token . isdigit ( ) : raise EBadCharacter ( ) 
    token = self . nextToken ( )
    if not token . isalpha ( ) : raise EBadCharacter ( ) 
    token = self . nextToken ( )
    if not token . isdigit ( ) : raise EBadCharacter ( ) 

    return 'complete', None
    
def complete ( self, token ) : pass
    
statemachine = StateMachine ( )
statemachine . addState ( local )
statemachine . addState ( complete, True )
statemachine . setStartState ( local )
}}}


== UK Postcode State Machine ==

{{{
#!python
from StateMachine import EBadCharacter, StateMachine

def postcodeFirstPart ( self, token ) :
    
    firstToken = token
    if not firstToken . isalpha ( ) : raise EBadCharacter ( )
    secondToken = self . nextToken ( )
    if secondToken . isalpha ( ) :
        thirdToken = self . nextToken ( )
        if thirdToken . upper ( ) == 'R' and secondToken . upper ( ) == 'I' and firstToken . upper ( ) == 'G' :
            token = self . nextToken ( )
            return "postcodeAfterBlank", token
        self . pushToken ( )
    else :
        self . pushToken ( )
    if not token . isalpha ( ) : raise EBadCharacter ( )
    token = self . nextToken ( )
    if not token . isdigit ( ) : raise EBadCharacter ( )
    token = self . nextToken ( )
    if token == ' ' : return "postcodeAfterBlank", token
    if not token . isalnum ( ) : raise EBadCharacter ( )
    token = self . nextToken ( )
    if token != ' ' : raise EBadCharacter ( )
    return "postcodeAfterBlank", token

def postcodeAfterBlank ( self, token ) :
    
    if token != ' ' : raise EBadCharacter ( ) 
    token = self . nextToken ( )
    if not token . isdigit ( ) : raise EBadCharacter ( ) 
    token = self . nextToken ( )
    if not token . isalpha ( ) : raise EBadCharacter ( ) 
    token = self . nextToken ( )
    if not token . isalpha ( ) : raise EBadCharacter ( ) 
    return 'complete', None
    
def complete ( self, token ) : pass
    
statemachine = StateMachine ( )
statemachine . addState ( postcodeFirstPart )
statemachine . addState ( postcodeAfterBlank )
statemachine . addState ( complete, True )
statemachine . setStartState ( postcodeFirstPart )
}}}

== Zip Code State Machine ==

{{{
#!python
from StateMachine import EBadCharacter, StateMachine

def local ( self, token ) :
    
    for c in range ( 5 ) :
        if not token . isdigit ( ) : raise EBadCharacter ( )
        if c < 4 : token = self . nextToken ( )
    return 'complete', None
    
def complete ( self, token ) :  pass

statemachine = StateMachine ( )
statemachine . addState ( local )
statemachine . addState ( complete, True )
statemachine . setStartState ( local )

}}}


== Picture Processing State Machine ==

{{{
#!python
from StateMachine import EBadCharacter, BADCHARACTER, STRINGTOOLONG, OK, StateMachine

##+ algebraic sign
##9 digit only
##A alphabetic only
##N alphanumeric only
##X anycharacter
##Y Y or N only
##? previous character not optional
##all other characters in the picture literal

def local ( self, token ) :
    
    picture = self . picture . upper ( )
    
    optional = [ ]
    for i, c in enumerate ( picture ) :
        if c == '?' : optional [ -1 + len ( optional ) ] = True
        else : optional . append ( False )
    picture = picture . replace ( '?', '' )
    
    for i, pictureChar in enumerate ( picture ) :
        if pictureChar == 'A' and token . isalpha ( ) : pass
        elif pictureChar == '9' and token . isdigit ( ) : pass
        elif pictureChar == '+' and token in [ '+', '-', ] : pass
        elif pictureChar == 'N' and token . isalnum ( ) : pass
        elif pictureChar == 'Y' and token in [ 'Y', 'N', ] : pass
        elif pictureChar == 'X' : pass
        else :
            if pictureChar in [ 'A', '9', '+', 'N', 'Y', 'X', ] :
                if optional [ i ] : continue
                else : raise EBadCharacter ( )
            else :
                if pictureChar == token  : pass
                else : 
                    if optional [ i ] : continue
                    else : raise EBadCharacter ( )
        if i + 1 < len ( picture ) :
            token = self . nextToken ( )
        else :
            break

    return 'complete', None
    
def complete ( self, token ) : pass
    
statemachine = StateMachine ( )
statemachine . addState ( local )
statemachine . addState ( complete, True )
statemachine . setStartState ( local )

if __name__ == "__main__" :
    
    import unittest
    
    class TestAgainstPostalCodes ( unittest . TestCase ) :
        
        def test1 ( self ) :
            statemachine . picture = 'a9a ?9a9'
            self . assertEqual ( statemachine . testString ( 'N0A 1P0' ), OK )

        def test2 ( self ) :
            statemachine . picture = 'a9a ?9a9'
            self . assertEqual ( statemachine . testString ( 'N0A1P0' ), OK )
    
        def test3 ( self ) :
            statemachine . picture = 'a9a ?9a9'
            self . assertEqual ( statemachine . testString ( '-0A1P0' ), BADCHARACTER )
    
        def test4 ( self ) :
            statemachine . picture = 'a9a ?9a9'
            self . assertEqual ( statemachine . testString ( '10A1P0' ), BADCHARACTER )
    
        def test5 ( self ) :
            statemachine . picture = 'a9a ?9a9'
            self . assertEqual ( statemachine . testString ( 'NaA1P0' ), BADCHARACTER )
    
        def test6 ( self ) :
            statemachine . picture = 'a9a ?9a9'
            self . assertEqual ( statemachine . testString ( 'N021P0' ), BADCHARACTER )
    
        def test7 ( self ) :
            statemachine . picture = 'a9a ?9a9'
            self . assertEqual ( statemachine . testString ( 'N0AaP0' ), BADCHARACTER )
    
        def test8 ( self ) :
            statemachine . picture = 'a9a ?9a9'
            self . assertEqual ( statemachine . testString ( 'N0A120' ), BADCHARACTER )
    
        def test9 ( self ) :
            statemachine . picture = 'a9a ?9a9'
            self . assertEqual ( statemachine . testString ( 'N0A1Pz' ), BADCHARACTER )

        def test10 ( self ) :
            statemachine . picture = 'a9a ?9a9'
            self . assertEqual ( statemachine . testString ( 'N0A1P00' ), STRINGTOOLONG )
        
        def test11 ( self ) :
            statemachine . picture = '+?999.?9?'
            self . assertEqual ( statemachine . testString ( '-111.1' ), OK )

        def test12 ( self ) :
            statemachine . picture = '+?999.?9?'
            self . assertEqual ( statemachine . testString ( '-1111' ), OK )
    
        def test13 ( self ) :
            statemachine . picture = '+?999.?9?'
            self . assertEqual ( statemachine . testString ( '-111.11' ), STRINGTOOLONG )
    
        def test14 ( self ) :
            statemachine . picture = '+?999.?9?'
            self . assertEqual ( statemachine . testString ( '+111.1' ), OK )
    
        def test15 ( self ) :
            statemachine . picture = '+?999.?9?'
            self . assertEqual ( statemachine . testString ( '111.1' ), OK )
    
        def test16 ( self ) :
            statemachine . picture = '+?999.?9?'
            self . assertEqual ( statemachine . testString ( '+111.1' ), OK )

    unittest . main ( )
}}}


== A CareFree State Machine -- Accepts Anything ==

{{{
#!python
from StateMachine import EBadCharacter, BADCHARACTER, STRINGTOOLONG, OK, StateMachine

class StateMachine :
    
    def testString ( self, str ) : return OK
        
statemachine = StateMachine ( )

if __name__ == "__main__" :

    import unittest
    
    class TestAgainstPostalCodes ( unittest . TestCase ) :
        
        def test1 ( self ) : self . assertEqual ( statemachine . testString ( 'N0A 1P0' ), OK )
        def test2 ( self ) : self . assertEqual ( statemachine . testString ( None ), OK )
        def test3 ( self ) : self . assertEqual ( statemachine . testString ( '' ), OK )
        def test4 ( self ) : self . assertEqual ( statemachine . testString ( '22' ), OK )
        def test5 ( self ) : self . assertEqual ( statemachine . testString ( '22x' ), OK )
        def test6 ( self ) : self . assertEqual ( statemachine . testString ( '2291' ), OK )
        def test7 ( self ) : self . assertEqual ( statemachine . testString ( '229x' ), OK )
        def test8 ( self ) : self . assertEqual ( statemachine . testString ( '22999' ), OK )

    unittest . main ( )

}}}


=== Comments ===

I welcome your comments. - [[Bill Bell]]