## Multiple specification

It is possible to make multiple simultaneous assignments by enclosing a list of variable names in parentheses on the left of an assignment arrow.

                 (A B C)„ 1 2 3
                 A
           1
                 B
           2
                 C
           3

A scalar to the right of the assignment arrow will be assigned to every item on the left. This is known as 'scalar extension'.

                 (A B C)„5
                 A
           5
                 B
           5
                 C
           5
                 (A B C)„ 'HI' 'THERE' 'FOLKS'
                 ½A                      (A assigned 'HI' and so on)
           2
                 (A B C)„›'HI' 'THERE' 'FOLKS'
                 ½A                      (A, B and C assigned the enclosed vector
           3                              to the right of the assignment arrow)

Caution:

Do not omit the parentheses if you are trying to do multiple specification, as in:

                 A B C„5

This expression will assign the value 5 to C and then attempt to evaluate the resultant expression. See also the discussion of binding strengths.

Topic: APLX Help : Help on APL language : APL Fundamentals : Multiple specification

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