deno compile for standalone executables - Step-by-Step Execution

Concept Flow - deno compile for standalone executables

Write Deno script

↓

Run: deno compile --output=app script.ts

↓

Deno compiles script

↓

Standalone executable created

↓

Run executable directly

↓

Program runs without Deno runtime

This flow shows how you write a Deno script, compile it into a standalone executable, and then run it without needing the Deno runtime installed.

Execution Sample

Deno

console.log("Hello from Deno!");

// Compile with:
// deno compile --output=hello hello.ts

// Run with:
// ./hello

This simple Deno script prints a message. We compile it into a standalone executable named 'hello' and then run it directly.

Execution Table

Step	Action	Input/Command	Result	Notes
1	Write script	console.log("Hello from Deno!");	Script file hello.ts created	Prepare code to compile
2	Compile script	deno compile --output=hello hello.ts	Executable 'hello' created	Deno bundles and compiles script into one file
3	Run executable	./hello	Outputs: Hello from Deno!	Runs without needing Deno installed
4	Exit	Program ends	Process terminates	Execution complete

💡 Program ends after printing message; standalone executable runs independently of Deno runtime

Variable Tracker

Variable	Start	After Compile	After Run	Final
hello.ts	File created with code	Unchanged	Unchanged	Unchanged
hello (executable)	Not present	Created	Executed	Exists on disk
Output	None	None	"Hello from Deno!"	Printed to console

Key Moments - 3 Insights

Why can I run the executable without installing Deno?

Because 'deno compile' bundles the Deno runtime and your script into one file, making it standalone as shown in execution_table step 2 and 3.

What happens if I change the script after compiling?

The executable won't change automatically. You must re-run 'deno compile' to update the standalone executable, as the compiled file is fixed after step 2.

Can I run the executable on a different OS?

No, the executable is OS-specific. You must compile on or for the target OS to get a working standalone executable.

Visual Quiz - 3 Questions

Look at the execution table, what command creates the standalone executable?

A deno compile --output=hello hello.ts

B ./hello

C deno run hello.ts

D deno install hello.ts

💡 Hint

Check Step 2 in the execution_table where the compile command is shown

At which step does the program output 'Hello from Deno!'?

A Step 1

B Step 2

C Step 3

D Step 4

💡 Hint

Look at the Result column in Step 3 of the execution_table

If you modify hello.ts after compiling, what must you do to update the executable?

A Run the executable again

B Recompile using deno compile

C Restart your computer

D Nothing, it updates automatically

💡 Hint

Refer to key_moments about updating the executable after code changes

Concept Snapshot

deno compile --output=app script.ts

- Bundles script and Deno runtime into one file
- Creates standalone executable for your OS
- Run executable directly without Deno installed
- Recompile after code changes
- Executable is OS-specific

Full Transcript

This visual execution shows how to create standalone executables with Deno. First, you write your Deno script. Then you run 'deno compile --output=app script.ts' to bundle your code and the Deno runtime into one executable file. This file can run on its own without needing Deno installed. When you run the executable, it behaves like your script would, printing output or doing tasks. If you change your script, you must recompile to update the executable. Also, the executable works only on the OS it was compiled for. This process lets you share Deno programs easily as single files.

Practice

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

easy

A. To create a standalone executable from a Deno script

B. To install Deno on your computer

C. To run a Deno script without compiling

D. To update Deno to the latest version

Solution

1. Step 1: Understand the role of deno compile

   This command packages a Deno script into a single executable file that can run without needing Deno installed.

2. Step 2: Compare other options

   Installing Deno, running scripts without compiling, or updating Deno are done by different commands, not deno compile.

3. Final Answer:

   To create a standalone executable from a Deno script -> Option A

4. Quick Check:

   deno compile = create executable [OK]

Hint: Remember: compile means make a runnable file [OK]

Common Mistakes:

• Confusing compile with install
• Thinking compile runs scripts directly
• Mixing compile with update commands

2. Which of the following is the correct syntax to compile a Deno script named app.ts into a standalone executable named app.exe on Windows?

easy

A. deno run --output app.exe app.ts

B. deno compile --output app.exe app.ts

C. deno build app.ts -o app.exe

D. deno compile app.ts --exe app.exe

Solution

1. Step 1: Recall the correct deno compile syntax

   The command uses deno compile --output [filename] [script] to specify output executable and source file.

2. Step 2: Check other options for errors

   deno run runs scripts but does not compile; deno build is not a valid command; --exe is not a recognized flag.

3. Final Answer:

   deno compile --output app.exe app.ts -> Option B

4. Quick Check:

   compile + --output + script = correct syntax [OK]

Hint: Use --output to name your executable [OK]

Common Mistakes:

• Using deno run instead of deno compile
• Wrong flag like --exe instead of --output
• Mixing command order

3. Given the command deno compile --output hello hello.ts and hello.ts contains console.log('Hello Deno!');, what will happen when you run the generated executable?

medium

A. It opens a browser window

B. It throws a syntax error

C. It does nothing

D. It prints 'Hello Deno!' to the console

Solution

1. Step 1: Understand the compiled executable behavior

   The executable runs the script code, so it will print the message to the console.

2. Step 2: Eliminate incorrect options

   No syntax error occurs because the script is valid; it does not open a browser or stay silent.

3. Final Answer:

   It prints 'Hello Deno!' to the console -> Option D

4. Quick Check:

   Compiled script output = printed message [OK]

Hint: Compiled executable runs script code as is [OK]

Common Mistakes:

• Expecting compile to change output
• Thinking compile causes errors
• Assuming GUI opens automatically

4. You tried to compile your script with deno compile --output myapp myapp.ts but got an error: PermissionDenied: read access to file 'myapp.ts' is required. What is the best way to fix this?

medium

A. Add --allow-read flag to the compile command

B. Run the command as administrator

C. Add --allow-run flag to the compile command

D. Rename the script file to myapp.js

Solution

1. Step 1: Understand the permission error

   The error says read access is denied for the script file, which is required to compile the source file.

2. Step 2: Identify correct permission flag

   --allow-read grants permission to read files, which is required to compile the script.

3. Final Answer:

   Add --allow-read flag to the compile command -> Option A

4. Quick Check:

   PermissionDenied = missing --allow-read [OK]

Hint: Use --allow-read to fix file access errors [OK]

Common Mistakes:

• Using --allow-run instead of --allow-read
• Thinking admin rights fix permission errors
• Renaming file without fixing permissions

5. You want to create a standalone executable for Linux from a Deno script server.ts on a Windows machine. Which command correctly compiles it for Linux?

hard

A. deno compile --output server-linux --platform linux server.ts

B. deno compile --output server-linux --os linux server.ts

C. deno compile --output server-linux --target x86_64-unknown-linux-gnu server.ts

D. deno compile --output server-linux --target linux-x64 server.ts

Solution

1. Step 1: Understand cross-compilation with deno compile

   You must specify the target triple for the desired OS and architecture using --target.

2. Step 2: Identify the correct target triple for Linux x64

   x86_64-unknown-linux-gnu is the standard target triple for 64-bit Linux.

3. Step 3: Check other options for invalid flags or values

   --platform and --os are not valid flags; linux-x64 is not a recognized target triple.

4. Final Answer:

   deno compile --output server-linux --target x86_64-unknown-linux-gnu server.ts -> Option C

5. Quick Check:

   Cross-compile uses --target with correct triple [OK]

Hint: Use --target with OS-arch triple for cross-compiling [OK]

Common Mistakes:

• Using invalid flags like --platform or --os
• Wrong target triple format
• Assuming compile auto-detects target OS