Chapter 7 - Control Statements
Control statements are statements that control when and how other statements are executed. Most control statements are compound statements--that is, statements that contain other statements.By default, AppleScript executes the statements in a script in sequence, one after the other. Control statements can change the order in which AppleScript executes statements by causing AppleScript to repeat or skip statements or go to a different statement.
This chapter describes the following control statements:
- Tell, which defines the default target to which commands are sent if no direct object is specified
- If, which allows you to execute or skip statements based on the outcome of one or more tests
- Repeat, which allows you to repeat a series of statements
- Try, which allows you to handle error messages
- Considering and Ignoring, which allow you to consider or ignore certain attributes, such as case, punctuation, and white space, in string comparisons
- With Timeout, which allows you to specify how long AppleScript waits for an application command or scripting addition to complete before stopping execution of the script and returning an error
- With Transaction, which allows you to take advantage of applications that support the notion of a transaction--a sequence of related events that should be performed as if they were a single operation
Chapter Contents
- Characteristics of Control Statements
- Tell Statements
- If Statements
- Repeat Statements
- Try Statements
- Kinds of Errors
- How Errors Are Handled
- Writing a Try Statement
- Signaling Errors in Scripts
- Considering and Ignoring Statements
- With Timeout Statements
- With Transaction Statements