Language Guide

CHAPTER 3

Values

Coercing Values 69

If you provide a command parameter or operand of the wrong class, AppleScript

automatically coerces the operand or parameter to the expected class, if possible.

For example, when AppleScript executes this statement,

repeat ( word 2 of document "Big" of application 

"Scriptable Text Editor") times

display dialog "Hello"

end repeat

it expects the number of times to be an integer. To coerce word 2 of

document "Big" of application "Scriptable Text Editor" to

an integer, AppleScript gets the value of word 2 of document "Big"

of application "Scriptable Text Editor"—a string—and then

coerces it to an integer, if possible.

Not all values can be coerced to all other classes of values. Figure 3-2 summarizes

the coercions that AppleScript supports. To use the ﬁgure, ﬁnd the class of the

value to be coerced in the column at the left. Search across the table to the column

labeled with the class to which you want to coerce the value. If there is a square

at the intersection, then AppleScript supports the coercion.

Reference values are not included in the table because applications determine

whether the value of an object speciﬁed by a reference value can be coerced to a

desired class.

For more information about each coercion, see the corresponding value class

deﬁnitions in this chapter.

Note

When coercing strings to values of class Integer, Number,

or Real or vice versa, AppleScript uses the current settings

in the Numbers control panel for decimal and thousands

to determine what separators to use in the string.

When coercing strings to values of class date or vice versa,

AppleScript uses the current settings in the Date & Time

control panel for date and time format. ◆