Here strings (<<<) in Bash Scripting - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to use a here string to pass the word 'hello' to the 'cat' command.

Bash Scripting

cat [1] 'hello'

Drag options to blanks, or click blank then click option'

A<<<

B<

C<<

D>>

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<<' which is for here documents, not here strings.

Using '<' which reads from a file, not a string.

The here string operator in bash is '<<<'. It passes the string on the right as input to the command on the left.

2fill in blank

medium

Complete the code to count the number of words in the string 'one two three' using a here string.

Bash Scripting

wc -w [1] 'one two three'

Drag options to blanks, or click blank then click option'

A>>

B<<

C<

D<<<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' which expects a filename, causing an error.

Using '<<' which expects a delimiter for a here document.

Using '<<<' passes the string as input to 'wc -w' which counts words.

3fill in blank

hard

Fix the error in the code to correctly use a here string to grep the word 'apple' in the string 'apple banana'.

Bash Scripting

grep apple [1] 'apple banana'

Drag options to blanks, or click blank then click option'

A<<

B<<<

C<

D>>

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' which expects a file, causing an error.

Using '<<' which is for here documents, not here strings.

The correct operator for passing a string as input is '<<<'.

4fill in blank

hard

Fill all blanks to create a here string that converts 'hello world' to uppercase using 'tr'.

Bash Scripting

tr [1] [2] [3] 'hello world'

Drag options to blanks, or click blank then click option'

A'[:lower:]'

B'[:upper:]'

C<<<

D<<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<<' instead of '<<<' for here string.

Swapping the character sets in 'tr'.

The 'tr' command translates characters from the first set to the second. The here string operator '<<<' passes the string as input.

5fill in blank

hard

Fill both blanks to create a dictionary of word lengths for words longer than 3 letters using a here string and Python.

Bash Scripting

python3 <<< "words = 'apple banana cat dog'.split()\nlengths = [1]: len([2]) for [2] in words if len({{BLANK_2}) > 3}\nprint(lengths)"

Drag options to blanks, or click blank then click option'

A{word

Bword

C}

Dwords

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'words' instead of 'word' as the loop variable.

Missing closing brace in the dictionary comprehension.

The dictionary comprehension syntax is {word: len(word) for word in words if len(word) > 3}. The here string passes the Python code as input.