deno doc for documentation - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to generate documentation for a file named mod.ts using deno doc.

Deno

deno doc [1]

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

Amod.ts

Brun.ts

Cindex.js

Dscript.py

Attempts:

3 left

💡 Hint

Common Mistakes

Using a file with the wrong extension like .js or .py

Forgetting to specify the file name after deno doc

The deno doc command followed by the file name mod.ts generates documentation for that file.

2fill in blank

medium

Complete the command to generate documentation in JSON format for app.ts.

Deno

deno doc --[1] app.ts

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

Ahtml

Bjson

Ctext

Dxml

Attempts:

3 left

💡 Hint

Common Mistakes

Using --html or --xml which are not supported flags for deno doc

Omitting the flag and getting default output

The --json flag outputs the documentation in JSON format.

3fill in blank

hard

Fix the error in the command to document the utils.ts file with deno doc.

Deno

deno [1] utils.ts

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

Adocs

Bdocument

Cdocsgen

Ddoc

Attempts:

3 left

💡 Hint

Common Mistakes

Typing 'docs' or 'document' instead of 'doc'

Using commands that do not exist in Deno

The correct command is deno doc. Other variants are invalid and cause errors.

4fill in blank

hard

Fill both blanks to generate documentation for server.ts including private symbols.

Deno

deno doc [1] [2]

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

A--json

B--unstable

C--private

Dserver.ts

Attempts:

3 left

💡 Hint

Common Mistakes

Using --unstable or --json which do not include private symbols

Forgetting to specify the file name

Placing the file before the flag

Use the --private flag and the file name server.ts to include private symbols in the documentation.

5fill in blank

hard

Fill all three blanks to generate JSON documentation for lib.ts including private symbols.

Deno

deno doc [1] [2] [3]

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

A--unstable

B--json

Clib.ts

D--private

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up the order of flags and file

Using --unstable instead of --private

The command requires the --json flag for JSON output, the --private flag to include private symbols, and the file name lib.ts.

Practice

1. What is the main purpose of the deno doc command?

easy

A. To run Deno scripts with debugging enabled

B. To install third-party Deno modules

C. To display easy-to-read documentation for your Deno code

D. To format Deno code automatically

Solution

1. Step 1: Understand the role of deno doc

   deno doc is designed to show documentation for Deno code in a clear and readable way.

2. Step 2: Compare with other options

   Running scripts, installing modules, or formatting code are done by other commands, not deno doc.

3. Final Answer:

   To display easy-to-read documentation for your Deno code -> Option C

4. Quick Check:

   Documentation = Display code info [OK]

Hint: Remember: doc means documentation, not running code [OK]

Common Mistakes:

• Confusing deno doc with running scripts
• Thinking it installs modules
• Assuming it formats code automatically

2. Which of the following is the correct way to write a comment that deno doc will use for documentation?

easy

A. # This is a hash comment

B. /* This is a block comment */

C. // This is a normal comment

D. /// This is a documentation comment

Solution

1. Step 1: Identify comment style for deno doc

   deno doc uses triple slash /// comments to generate documentation.

2. Step 2: Check other comment types

   Single slashes and block comments are normal comments, hash comments are not valid in Deno.

3. Final Answer:

   /// This is a documentation comment -> Option D

4. Quick Check:

   Triple slash = doc comment [OK]

Hint: Use triple slashes for doc comments with deno doc [OK]

Common Mistakes:

• Using single or block comments for documentation
• Using hash (#) comments from other languages
• Not using any comment before functions or variables

3. Given this code snippet, what will deno doc example.ts show for the function add?

/// Adds two numbers
function add(a: number, b: number): number {
  return a + b;
}

medium

A. Function add(a: number, b: number): number - Adds two numbers

B. No output because comments are ignored

C. Syntax error due to missing export

D. Only the function signature without comments

Solution

1. Step 1: Check comment usage

   The triple slash comment above the function is used by deno doc to show description.

2. Step 2: Understand output format

   deno doc shows the function signature plus the comment as description.

3. Final Answer:

   Function add(a: number, b: number): number - Adds two numbers -> Option A

4. Quick Check:

   Doc comment + signature = detailed output [OK]

Hint: Doc comments appear with function signatures in output [OK]

Common Mistakes:

• Thinking comments are ignored
• Assuming export is required for doc
• Expecting only signature without comments

4. You run deno doc myfile.ts but get no documentation output. What is the most likely cause?

medium

A. You forgot to install Deno

B. The file has no triple slash /// comments

C. The file is missing a main function

D. The file uses single-line comments only

Solution

1. Step 1: Check comment style in the file

   deno doc requires triple slash /// comments to generate documentation.

2. Step 2: Understand other options

   Missing main function or single-line comments do not affect deno doc output; Deno must be installed to run the command.

3. Final Answer:

   The file has no triple slash /// comments -> Option B

4. Quick Check:

   No triple slash comments = no doc output [OK]

Hint: Check for triple slash comments if doc output is empty [OK]

Common Mistakes:

• Assuming main function is needed for documentation
• Confusing single-line comments with doc comments
• Not verifying Deno installation before running command

5. You want to generate JSON documentation for a remote Deno module at https://deno.land/std@0.200.0/fs/mod.ts. Which command will correctly produce JSON output?

hard

A. deno doc --json https://deno.land/std@0.200.0/fs/mod.ts

B. deno doc https://deno.land/std@0.200.0/fs/mod.ts --json

C. deno doc --json -r https://deno.land/std@0.200.0/fs/mod.ts

D. deno doc -j https://deno.land/std@0.200.0/fs/mod.ts

Solution

1. Step 1: Identify correct flag usage for JSON output

   The --json flag must come before the file or URL argument in deno doc.

2. Step 2: Check command syntax

   deno doc --json https://deno.land/std@0.200.0/fs/mod.ts places --json before the URL, which is correct. Other options either place flags incorrectly or use invalid flags.

3. Final Answer:

   deno doc --json https://deno.land/std@0.200.0/fs/mod.ts -> Option A

4. Quick Check:

   --json before URL = correct syntax [OK]

Hint: Put --json before file or URL for JSON output [OK]

Common Mistakes:

• Placing --json after the URL
• Using shorthand -j which is invalid
• Adding extra flags like -r that don't exist