Repeat Statement :Repeat
The simplest type of :Repeat loop is as follows. This example executes lines [3-5] 100 times. Notice that as there is no conditional test at the beginning of a :Repeat structure, its code statements are executed at least once.
[1] I←0
[2] :Repeat
[3] expr1
[4] expr2
[5] I←I+1
[6] :Until I=100
You can have multiple conditional tests at the end of the loop by adding :AndIf or :OrIf expressions. The following example will read data from a native file as 80-character records until it reaches one beginning with the text string 'Widget' or reaches the end of the file.
[1] :Repeat
[2] REC←⎕NREAD ¯1 82 80
[3] :Until 'Widget'≡6⍴REC
[4] :OrIf 0=⍴REC
A :Repeat structure may be terminated by an :EndRepeat (or :End) statement in place of a conditional expression. If so, your code must explicitly jump out of the loop using a :Leave statement or by branching. For example:
[1] :Repeat
[2] REC←⎕NREAD ¯1 82 80
[3] :If 0=⍴REC
[4] :OrIf 'Widget'≡6⍴REC
[5] :Leave
[6] :EndIf
[7] :EndRepeat