Vocabulary/curlyrtco

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}: Curtail

Rank Infinity -- operates on x and y as a whole, by items of y -- WHY IS THIS IMPORTANT?



Drops the last item from y

   }: 'abc'
ab

Common Uses

1. Remove the last atom from a list.

Drop unwanted final LF from otherwise convenient noun definition

   V=: 0 : 0
abc
def
ghi
)
   <V           NB. See the (non-printable) LF at the end of the boxed string
+------------+
|abc def ghi |
+------------+
   <}: V        NB. Delete it
+-----------+
|abc def ghi|
+-----------+

2. Remove the last row from a table

   ]t =: _2 ]\ 'Fred';20;'John';50;'Total';70
+-----+--+
|Fred |20|
+-----+--+
|John |50|
+-----+--+
|Total|70|
+-----+--+
   }: t
+----+--+
|Fred|20|
+----+--+
|John|50|
+----+--+

3. Applied at rank 1, remove the last item from each row of a table

   }:"1 i. 3 3
0 1
3 4
6 7

Related Primitives

Head ({. y), Behead (}. y), Tail ({: y)


More Information

1.  }:y is identical to  _1}.y .


Details

1. The rank of  }:y is the same as the rank of y unless y is an atom, in which case  }:y is an empty list (with the same type as y).

2. If y has no items then  }:y is the same as y .