Micropython String

[srogers]

I was looking at print formatting with MicroPython and RP2.

Specifically I was trying to use:

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print("foo".ljust(50))

I was unable to do thing because the REPL reports that there is no method ljust for str.

And, sure enough, in MicroPython 1.18 ljust (and rjust) do not exist as methods to str.

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help ("foo")
object foo is of type str
  encode -- <function>
  find -- <function>
  rfind -- <function>
  index -- <function>
  rindex -- <function>
  join -- <function>
  split -- <function>
  splitlines -- <function>
  rsplit -- <function>
  startswith -- <function>
  endswith -- <function>
  strip -- <function>
  lstrip -- <function>
  rstrip -- <function>
  format -- <function>
  replace -- <function>
  count -- <function>
  partition -- <function>
  rpartition -- <function>
  center -- <function>
  lower -- <function>
  upper -- <function>
  isspace -- <function>
  isalpha -- <function>
  isdigit -- <function>
  isupper -- <function>
  islower -- <function> 

Why is there no ljust or rjust, when it is shown as examples to use for formatting?

[stijn]

Perhaps you were looking at CPython examples?

MicroPython indeed does not implement those functions: http://docs.micropython.org/en/latest/g ... s.html#str

[pythoncoder]

So write your own:

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def rjust(s, n):
    return "".join((" "*(n - len(s)), s))
print(rjust("foo", 50))
                                               foo

Or as a one-liner

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ljust = lambda s, n : "".join((s, " "*(n - len(s))))

[bulletmark]

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print(f'{"foo":<50s}')

[pythoncoder]

Much better