Specifying a range

Labels allow you to specify a line or a range of lines on a primary command. You can specify two labels to define a range of lines to be processed on these commands:


CHANGE   DELETE   EXCLUDE
FIND     LOCATE   REPLACE
RESET    SORT     SUBMIT

The range operand is always optional. If you do not specify a range, it defaults to .ZFIRST and .ZLAST. For example, the command:

CHANGE ALL 'TEST' 'FINAL'

starts at the first line of the data being edited and scans all lines up to and including the last line, changing all occurrences of TEST to FINAL.

However, the command:

CHANGE .ZCSR .ZLAST ALL 'TEST' 'FINAL'

specifies a range, and is thus interpreted differently. The command changes only the last part of the data.

When you use labels to specify a range, you must always use two labels to define the first and last lines, inclusively. To process a single line, repeat the label:

CHANGE ALL " " "_" .A .A

The command in the previous example is interpreted as Change all blanks to underscores on the .A line.

The order in which you specify the labels is not important. The editor assumes that the line closer to the beginning of the data set is the first line of the range, and the line closer to the end of the data set is the last.

A common error when using a range is to assume that the search begins at the first character of the line with the first label. Remember, however, that the default is NEXT and that the search starts at the cursor location. Lines outside the range are logically the same as the TOP OF DATA and BOTTOM OF DATA lines. Use the FIRST, LAST, or PREV operands to ensure that the search begins within the range.