Split and join methods in Ruby - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the split method do in Ruby?

The split method breaks a string into an array of smaller strings based on a separator you provide. If no separator is given, it splits on whitespace by default.

beginner

How does the join method work in Ruby?

The join method takes an array of strings and combines them into one string, inserting a separator between each element if you provide one.

beginner

Example: What is the result of "apple,banana,carrot".split(",")?

It returns the array ["apple", "banana", "carrot"] by splitting the string at each comma.

beginner

Example: What does ["red", "green", "blue"].join("-") return?

It returns the string "red-green-blue" by joining the array elements with a dash between them.

intermediate

Why are split and join useful together?

You can use split to break a string into parts, change or process those parts, then use join to put them back together into a new string.

What is the default separator for the split method in Ruby if none is provided?

A Comma

B Period

C Whitespace (spaces, tabs, newlines)

D No separator, returns whole string in array

If you don't give a separator, split divides the string at whitespace by default.

What will "one two three".split return?

A Error

B ["one two three"]

C ["o", "n", "e"]

D ["one", "two", "three"]

Without an argument, split splits on spaces, so it returns an array of words.

What does ["a", "b", "c"].join return?

A "a,b,c"

B "abc"

C "a b c"

D Error

Without a separator, join combines elements directly with no spaces.

Which method would you use to turn a string into an array?

A split

B join

C map

D select

split breaks a string into an array based on a separator.

Which method would you use to combine an array of strings into one string?

A join

B split

C reduce

D flatten

join combines array elements into a single string.

Explain how you can use split and join together to change a sentence.

Think about breaking a sentence into words, changing words, then making a new sentence.

Describe what happens when you call split without any arguments on a string.

What does Ruby consider whitespace?