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Other remarks

  1. The WHILE:  and WEND:  commands may not be used during one-line FOR:  and one-line IF:  statements.
  2. The while ...wend construction is similar to the repeat ...until construction, except that the test for processing the enclosed body of commands is at the start rather than the end of the loop. Therefore the body of commands enclosed in a while ...wend loop might not be processed, whereas the body of commands enclosed in a repeat ...until loop are always processed at least once.
  3. The current status of while ...wend constructions are cleared whenever the RESTART:  command is issued, but not when a CLEAR:  command is issued.
  4. There are no limits to the number of active while ...wend loops, subject to memory limitations.
  5. For interactive work, when you issue a WHILE:  command, the program simply copies your further inputs (without obeying any commands) until you input a WEND:  command to mark the end of the loop. Thereafter the loop is processed in the usual way. The interactive WHILE: -WEND:  construction causes the copying of command lines to a temporary file. Every line is copied as an original, without any parsing: errors in the command syntax may be reported, but the process will continue. During such interactive work, the following prompt  is used:

    BD/ tex2html_wrap_inline33712

    to indicate to you that the program is awaiting a WEND:  statement before processing your inputs.

       



David Wooff
Wed Oct 21 15:14:31 BST 1998