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vslice

Definition: sequence res = vslice(sequence source, object column, error_control=0)
Description: Extract a specified column or vertical slice from a sequence.
source: the sequence from which to extract a vertical column.
column: positive integer or pair of integers (latter is not Euphoria-compatible).
error_control: 0 => crash, integer => return short, sequence => replacement[s].

Returns a sequence or string of at most length(source). The result will be a string if column is an integer and source is either a list of strings or each element extracted happens to be an integer(/character) in the range 0..255.
pwa/p2js: Supported.
Example: 
sequence s = {{5,1},
              {5,2},
              {5,3},
              4}
?vslice(s,2,1)          -- prints {1,2,3} -- (omitting error_control crashes)
?vslice(s,1,1)          -- prints {5,5,5}           --  ""
?vslice(s,{1,2},1)      -- prints {{5,1},{5,2},{5,3}} --   ""
?vslice(s,{1,2},{1})    -- prints {{5,1},{5,2},{5,3},1} --   ""
(Technically the first two results are binary strings that ? prettifies to look like dword-sequences, as opposed to "\x01\x02\x03", x"010203", "\x05\x05\x05", or x"050505".)
Implementation: See builtins\vslice.e (an autoinclude) for details of the actual implementation.
See Also: columnize
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