Labels
Labels
Any line of ObjectScript code can optionally include a label (also known as a tag). A label serves as a handle for referring to that line location in the code. A label is an identifier that is not indented; it is specified in column 1. All ObjectScript commands must be indented.
Labels have the following naming conventions:
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The first character must be an alphanumeric character or the percent character (%). Note that labels are the only ObjectScript names that can begin with a number. The second and all subsequent characters must be alphanumeric characters. A label may contain Unicode letters.
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They can be up to 31 characters long. A label may be longer than 31 characters, but must be unique within the first 31 characters. A label reference matches only the first 31 characters of the label. However, all characters of a label or label reference (not just the first 31 characters) must abide by label character naming conventions.
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They are case-sensitive.
A block of ObjectScript code specified in an SQL command such as CREATE PROCEDURE or CREATE TRIGGER can contain labels. In this case, the first character of the label is prefixed by a colon (:) specified in column 1. The rest of the label follows the naming and usage requirements describe here.
A label can include or omit parameter parentheses. If included, these parentheses may be empty or may include one or more comma-separated parameter names. A label with parentheses identifies a procedure block.
A line can consist of only a label, a label followed by one or more commands, or a label followed by a comment. If a command or a comment follows the label on the same line, they must be separated from the label by a space or tab character.
The following are all unique labels:
maximum
Max
MAX
%controlYou can use the $ZNAME function to validate a label name. Do not include parameter parentheses when validating a label name.
Labels are useful for identifying sections of code and for managing flow of control. See Legacy Code and Labels.
