AppleScript: The Definitive Guide

Comparison Operators

The result is a boolean. The nature of comparisons involving strings can be influenced by a considering clause; see Chapter 12.

Lists are ordered, but records are not:

{1, 2} = {2, 1} -- false
{name:"Matt", age:"49"} = {age:"49", name:"Matt"} -- true

The equality (=) and inequality (≠) operators do not coerce their operands; operands may be of any datatype, and operands of different datatypes are unequal. So, for example:

{"2"} = 2 -- false

The first operand is a list; the second operand is a number; no coercion takes place; therefore the operands are not equal, and the comparison is false.

With the other comparison operators, operands must be a string, a number, or a date; the first operator is coerced to a string, a number, or a date, and then the second operator is coerced to match the datatype of the first:

{"2"} ≥ 2 -- true

The first operand is a list of one string, so it is coerced to a string. Now the second operand is coerced to a string; the two strings are equal and the comparison is true.

Thus, although you cannot use the equality operator to learn whether two values would be equal if implicitly coerced to the same datatype, you can work around the problem like this:

{"2"} ≤ 2 and {"2"} ≥ 2