WHILE <relational operator> <arithmetic expression>

Characters are scanned as long as they pass the test. For example, the following statement scans the characters pointed to by P as long as a period (.) is not encountered:

SCAN P WHILE NEQ "."

UNTIL <relational operator> <arithmetic expression>

Characters are scanned until a source character passes the test. For example, the following statement scans the characters pointed to by P until a blank character is encountered:

SCAN P:P UNTIL = " "

P is updated to point to the blank character that passed the test.

WHILE IN <truth set table>

Characters are scanned as long as they are members of the truth set. For example, the following statement scans the characters pointed to by P as long as they are members of the truth set ALPHA8:

SCAN P:P WHILE IN ALPHA8

P is updated to point to the first character that is not a member of ALPHA8.

UNTIL IN <truth set table>

Characters are scanned until a source character is found that is a member of the truth set. For example, the following statement scans the characters pointed to by P until a member of the truth set ALPHA8 is encountered:

SCAN P:P UNTIL IN ALPHA8

P is updated to point to the first character that is a member of ALPHA8.