Substring/Top and tail: Difference between revisions
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m (→{{header|Python}}: ( comprehension in lieu of ap (<*>) )) |
m (Reverted an inadvertent edit) |
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=={{header|Python}}== |
=={{header|Python}}== |
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<lang python>print "knight"[1:] # strip first character |
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print "socks"[:-1] # strip last character |
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print "brooms"[1:-1] # strip both first and last characters</lang> |
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Or, composing atomic functional expressions for these slices: |
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<lang python>from functools import (reduce) |
<lang python>from functools import (reduce) |
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def main(): |
def main(): |
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print ( |
print ( |
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ap([tail, init, compose(init)(tail)])( |
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["knights"] |
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) |
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) |
) |
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def init(xs): |
def init(xs): |
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return xs[:-1] |
return xs[:-1] |
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# ap (<*>) :: [(a -> b)] -> [a] -> [b] |
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def ap(fs): |
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return lambda xs: reduce( |
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lambda a, f: a + reduce( |
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lambda a, x: a + [f(x)], xs, [] |
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), fs, [] |
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) |
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