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14.3 DO REPEAT

     DO REPEAT dummy_name=expansion....
             ...
     END REPEAT [PRINT].
     
     expansion takes one of the following forms:
             var_list
             num_or_range...
             'string'...
             ALL
     
     num_or_range takes one of the following forms:
             number
             num1 TO num2

DO REPEAT repeats a block of code, textually substituting different variables, numbers, or strings into the block with each repetition.

Specify a dummy variable name followed by an equals sign (‘=’) and the list of replacements. Replacements can be a list of existing or new variables, numbers, strings, or ALL to specify all existing variables. When numbers are specified, runs of increasing integers may be indicated as num1 TO num2, so that ‘1 TO 5’ is short for ‘1 2 3 4 5’.

Multiple dummy variables can be specified. Each variable must have the same number of replacements.

The code within DO REPEAT is repeated as many times as there are replacements for each variable. The first time, the first value for each dummy variable is substituted; the second time, the second value for each dummy variable is substituted; and so on.

Dummy variable substitutions work like macros. They take place anywhere in a line that the dummy variable name occurs. This includes command and subcommand names, so command and subcommand names that appear in the code block should not be used as dummy variable identifiers. Dummy variable substitutions do not occur inside quoted strings, comments, unquoted strings (such as the text on the TITLE or DOCUMENT command), or inside BEGIN DATA...END DATA.

Substitution occurs only on whole words, so that, for example, a dummy variable PRINT would not be substituted into the word PRINTOUT.

New variable names used as replacements are not automatically created as variables, but only if used in the code block in a context that would create them, e.g. on a NUMERIC or STRING command or on the left side of a COMPUTE assignment.

Any command may appear within DO REPEAT, including nested DO REPEAT commands. If INCLUDE or INSERT appears within DO REPEAT, the substitutions do not apply to the included file.

If PRINT is specified on END REPEAT, the commands after substitutions are made are printed to the listing file, prefixed by a plus sign (‘+’).