Hello,
There's a word called 'flatten' which flattens sequences.
Here's the implementation of 'flatten' from sequences.deep :
----------------------------------------------------------------------
: deep-each ( obj quot -- )
[ call ] 2keep over branch?
[ [ deep-each ] curry each ] [ 2drop ] if ; inline
: deep-subset ( obj quot -- seq )
over >r
pusher >r deep-each r>
r> dup branch? [ like ] [ drop ] if ; inline
: flatten ( obj -- seq )
[ branch? not ] deep-subset ;
----------------------------------------------------------------------
Here's another version of flatten. One difference is that it uses a 'push'
with effect ( vec obj -- vec ). It also doesn't maintain the type of the
sequences.
----------------------------------------------------------------------
: push-or-transfer ( vec obj -- vec )
dup branch?
[ transfer ]
[ push ]
if ;
: transfer ( vec seq -- vec ) [ push-or-transfer ] each ;
: flatten ( seq -- seq ) [ length <vector> ] [ ] bi transfer ;
----------------------------------------------------------------------
Ed
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