Text

Texts in programs are called strings: characters strung together like beads on a string. You know that you write them in double quotes "…" or single quotes '…'. You can store a text in a variable like any other value, and join texts with ..:

local farm = "Sunflower Farm"
local crop = "pumpkins"
local sign = crop .. " from " .. farm
print(sign)
print(farm .. crop)

This prints:

pumpkins from Sunflower Farm
Sunflower Farmpumpkins

.. doesn't add any spaces. Write them into the texts yourself, as in " from ". And + doesn't join texts: "Sunflower" + "Farm" ends with the error attempt to add a 'string' with a 'string', because + only adds numbers.

A text in double quotes ends at the next double quote. If you need quotes inside it, there are two ways: put the text in the other kind of quotes, or write a backslash \ in front of the quote:

print('Emma says: "Welcome!"')
print("Emma says: \"Welcome!\"")
print("Grandpa Joe's barn")

This prints:

Emma says: "Welcome!"
Emma says: "Welcome!"
Grandpa Joe's barn

Without the backslash, the text ends too early:

print("Emma says: "Welcome!"")

Lua reports:

main.lua:1: ')' expected near 'Welcome'

The text ended after Emma says: , and then Lua found the word Welcome where it expected the closing parenthesis.

A backslash and the character after it make an escape sequence: two characters in the code that stand for one special character in the text:

• \n is a new line,
• \t is a tab,
• \" and \' are quotes,
• \\ is one backslash.

print("Carrots\nPotatoes\tPumpkins")

This prints:

Carrots
Potatoes	Pumpkins

The length of a text is given by # in front of it:

local farm = "Sunflower Farm"
print(#farm)
print(#"Rex")
print(#"")

This prints:

14
3
0

The space counts too, and "" is an empty text, with no characters at all. Strictly speaking, # counts bytes, the small units in which the computer stores a text. A plain letter, digit, space or punctuation mark takes one byte, but a letter with an accent, such as the é in café, takes two, so #"café" is 5. You'll learn how to count such letters in the lesson on strings.