python - What does this code mean with stripping leading zeroes? - 


eval("".join(token.lstrip('0') token in s.split()))

where s '02 + 00030 - 76'.

all know strips zeroes in front of 02 , 00030 can evaluate 2+30-76. however, don't understand how this. explain combination of functions me?
much. 

for token in s.split()

s.split() evaluates ['02', '+', '00030', '-', '76']

then token.strip('0') converts list - ['2', '+', '30', '-', '76'] removing leading 0s each token.

finally "".join([..]) joins them '2+30-76'.

eval evaluates expression integer.

ps: bad idea use eval on unsanitized user input text. imagine happen if user enters malicious code input.


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