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Python

Abid Rather
Abid Rather
4,719 Points
Posted by Abid Rather
Abid Rather
4,719 Points

Help with Morse.py. Appreciate the help

Problem is to convert, for instance, "dash-dot" string to ["_" , "."] by defining a class method from_String. My static method does not seem to work. Appreciate your help in pointing out whats wrong with my code

morse.py 
class Letter:
    def __init__(self, pattern=None):
        self.pattern = pattern

    def __iter__(self):
        yield from self.pattern

    def __str__(self):
        output = []
        for blip in self:
            if blip == '.':
                output.append('dot')
            else:
                output.append('dash')
        return '-'.join(output)
    @staticmethod
    def from_string(cls, string_arg):
        output = []
        for word in string_arg.split('-'):
            if word == "dash":
                output.append('_')
            else:
                output.append('.')
        return cls(','.join(output))



class S(Letter):
    def __init__(self):
         pattern = ['.', '.', '.']
         super().__init__(pattern)

1 Answer

andren
andren
28,558 Points
andren
andren
28,558 Points

There are two issues in your code:

  1. For this method you should use the @classmethod annotation, not @staticmethod. The difference between them is that with a class method Python passes the class as the first argument automatically, with a static method the class is not sent automatically.
  2. The Letter constructor takes an array as its argument, but you are passing it a string since you use join on the array you create. There is no need to convert the array before passing it to the constructor.

If you fix those two issues like this:

class Letter:
    def __init__(self, pattern=None):
        self.pattern = pattern

    def __iter__(self):
        yield from self.pattern

    def __str__(self):
        output = []
        for blip in self:
            if blip == '.':
                output.append('dot')
            else:
                output.append('dash')
        return '-'.join(output)

    @classmethod # @staticmethod changed to @classmethod
    def from_string(cls, string_arg):
        output = []
        for word in string_arg.split('-'):
            if word == "dash":
                output.append('_')
            else:
                output.append('.')
        return cls(output) # Don't turn the array into a string


class S(Letter):
    def __init__(self):
         pattern = ['.', '.', '.']
         super().__init__(pattern)

Then your code will work.

Abid Rather
Abid Rather
4,719 Points
Abid Rather
Abid Rather
4,719 Points

Absolutely. Thanks for your help Andren!