flatten
| Definition: | sequence res = flatten(sequence s, res="") |
| Description: |
Remove all nesting from a sequence.
Returns a string or a sequence of atoms. By default, if all (nested) elements of s are string or integers in the range 0..255, a [binary] string will be returned. The optional res parameter allows that behaviour to be overriden, ie flatten(s,{}) returns a dword-sequence. It is also possible to provide a starting prefix, eg flatten({"a",{"b",{"c"}}},"flattened:") returns "flattened:abc". |
| Comments: | Empty sub-sequences are stripped out entirely.
Unlike the (broken) Euphoria version of flatten, there is no optional delimiter: for something like {"this","that"} -> "this\nthat", use join(), which is usually much more appropriate for string processing. |
| Example: | You can use flatten() on a tree-like structure, e.g. |
?flatten({10,{ 13, {45}}, {84.1, {}, 33.2}}) -- {10,13,45,84.1,33.2}
?flatten({10,{ 13, {45}}, {84, {}, 33}}) -- "\n\r-T!"
?flatten({10,{ 13, {45}}, {84, {}, 33}},{}) -- {10,13,45,84,33}
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| Implementation: | See builtins\pflatten.e (an autoinclude) for details of the actual implementation. |
| See Also: | join |