() is less than ()

The correct title of this article is () < (). The Scratch Wiki uses a different title because of technical restrictions.

() < ()
() \< ()
Category	Operators
Type	Boolean
Introduced in	11Oct03 (0.x)

The () < () block is an Operators block and a Boolean block. The block reports true if the first value is less than the second value and false otherwise.

This block can compare both numbers and strings, which are ordered alphabetically. In Scratch 1.3 and previous versions, it only accepted numbers.

This block has complicated behavior to handle the many kinds of values that can be compared. This sometimes results in unintuitive results, such as the comparison of long strings that are valid numbers.

Example Uses

Some common uses for the () < () block are below:

• Sorting
• Comparing different variables

if <(score 1) < (score 2)> then
    say [Player 2 wins!]
else
    say [Player 1 wins!]
end

• Checking that a value is within a given range

<<[0] < (score)> and <(score) < [10]>> // true if score is between 0 and 10

Comparison

The block first tries to cast the inputs to numbers. If both are not valid as double-precision floating-point numbers, they are compared as strings without case sensitivity.

Comparing Numbers

Numbers will be compared as expected unless they are very large:

<[100] < [101]> // returns true
<[100000000000000000] < [100000000000000001]> // returns false

This is because when the numbers are stored as double-precision floating-point numbers a loss of precision can occur, leading to the closest representation of both inputs being the same value. In very large numbers this could be the value Infinity.

This can be avoided by adding a letter at the beginning, which forces Scratch to only use a text comparison and not a number comparison:

<(join [a] [100000000000000000]) < (join [a] [100000000000000001])> // returns true

Comparing Text

Text is compared alphabetically:

<[a] < [b]> // returns true
<[b] < [a]> // returns false

The Empty Value

The empty value will always be considered smaller than other values:

<[] < [10]> // returns true
<[10] < []> // returns false

Workaround

Main article: List of Block Workarounds

The block can be replicated with the greater than operator and swapping the inputs:

<[4] < [5]> // returns true
<[5] > [4]> // returns true

Less Than Or Equal To

Sometimes it is necessary to know if a value is less than or equal to another value, but there is no block to do so. This can be done as follows:

<not <[4] > [5]>> // 4 ≤ 5 returns true

See Also

• () = ()
• () > ()