() Contains ()? (List block)

() Contains ()?
[ v] contains []?
Category	List
Type	Boolean
Introduced in	1.4

This article is about the list block. For the Operators block that checks if one string contains the other, see () Contains ()? (Operators block).

The () contains ()? block is a boolean block and a list block. The block checks if any items in the specified list are equal to the given text — if at least one of them is, the block returns true; if none of them are, it returns false. The item must contain the exact text; for example, "abc" would not work if the item contained "abcde". This block was case-sensitive in Scratch 1.4.

Example Uses

This block can be used to check whether an item is in a list or not.

Some common uses for the () Contains ()? block:

• Scanning lists

if <[lunch v] contains [spinach]?> then
say [Yuck! Spinach!]
end

• Checking if an item already exists before adding it to an inventory

if <not <[collection v] contains [fan]?>> then
add [fan] to [collection v]
else
say [I already have a fan in my collection.]
end

• Making sure an item is in an inventory before performing a command.

if <[collection v] contains [fan]?> then
broadcast (action v)
else
say [It's too far to reach the pile of sand on that platform.]
end

• Checking if a selected level is locked or unlocked for the player.

ask [which level would you like to play?] and wait
if <[unlocked levels v] contains (answer)?> then
broadcast(start level v)
else
say [The level you chose hasn't been unlocked yet! Play the previous level to play this one.

Case Sensitivity

This block is not case sensitive in its checks. This means that if a list contains exactly "apple", the below will occur:

<[list v] contains [APPLE]> // reports true
<[list v] contains [apple]> // reports true
<[list v] contains [Apple]> // reports true

Workaround

Main article: List of Block Workarounds

This block can be replicated with the following code:

set [count v] to [1]
repeat until <<(count) > (length of [list v])> or <(item (count) of [list v]) = (thing)>>
  change [count v] by (1)
end
set [report v] to <(item (count) of [list v]) = (thing)>

When it is needed,<(report) = [true]> is placed into the boolean insert.

However, a simpler workaround is to just use the (item # of [thing] in [list v]), which can be inserted into boolean inserts:

if (item # of (. . .:: grey) in [list v]) then
    . . .
end