Which MIME types are related to file extension ".wast"?
The .wast file extension is associated with 2 MIME types:
application/wasm, text/x-common-lisp.
A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.
About .wast Files
WAST files are text-based source files used for WebAssembly programming.
They contain code written in a Lisp-like syntax. This makes them easier to read and edit than their binary .wasm counterparts.
- Primary Use: Writing, testing, and debugging WebAssembly modules.
- Syntax: Uses S-expressions similar to common Lisp, which is why one MIME type is text/x-common-lisp.
- MIME Association: Although application/wasm is mainly for binary modules, it links WAST files to the WebAssembly ecosystem.
- Tools: Software like the WebAssembly Binary Toolkit (WABT) can compile and convert them to standard .wasm files.
Relationship between file extension and MIME type
A file extension is a suffix at the end of a filename that indicates what type of file it is. File extensions help both users and operating systems identify what application should be used to open the file.
File extensions are typically separated from the filename by a period (dot) and consist of 2-4 characters, though they can be longer. For example, in the filename "document.pdf", ".pdf" is the file extension.
File extensions are closely related to MIME types, as they both serve to identify the format of a file. However, while MIME types are used primarily by web browsers and servers, file extensions are used by operating systems and applications.
Associated MIME types
application/wasm, text/x-common-lisp
FAQs
What is a .wast file used for?
A .wast file is a human-readable text representation of WebAssembly code, primarily used by developers to write, debug, and test modules. Unlike the binary .wasm format, which is designed for machine execution, the .wast format allows humans to read the logic using a syntax similar to Lisp.
How do I open and edit a .wast file?
Because .wast files contain plain text, you can open them in any text editor such as Visual Studio Code, Sublime Text, or Notepad++. For the best experience, install a WebAssembly syntax highlighting extension to make the S-expression structure easier to read.
How can I convert a .wast file to a binary .wasm file?
You can compile a .wast file into a binary .wasm file using the WebAssembly Binary Toolkit (WABT). specifically utilizing the command-line tool wat2wasm. This process converts the text-based source into the application/wasm format required by web browsers.
What is the difference between .wast and .wat extensions?
While both formats describe WebAssembly in text, .wat is the standard extension for a pure WebAssembly module. The .wast extension is historically broader and is often used for test suites (supersets) that include assertions and harness commands not present in the standard binary format.
Can web browsers run .wast files directly?
No, modern web browsers like Google Chrome and Mozilla Firefox are optimized to execute compiled .wasm binaries. To run code written in a .wast file on the web, you must first compile it or use a specific JavaScript library to parse the text format on the fly.
Why is the MIME type text/x-common-lisp associated with this file?
WebAssembly text format uses S-expressions (nested lists within parentheses) to structure data, which is identical to the syntax used by Lisp programming languages. As a result, some systems identify the file as text/x-common-lisp to apply appropriate syntax coloring.
General FAQ
What is a MIME type?
A MIME (Multipurpose Internet Mail Extensions) type is a standard that indicates the nature and format of a document, file, or assortment of bytes. MIME types are defined and standardized in IETF's RFC 6838.
MIME types are important because they help browsers and servers understand how to process a file. When a browser receives a file from a server, it uses the MIME type to determine how to display or handle the content, whether it's an image to display, a PDF to open in a viewer, or a video to play.
MIME types consist of a type and a subtype, separated by a slash (e.g., text/html, image/jpeg, application/pdf). Some MIME types also include optional parameters.
How do I find the MIME type for a file?
You can check the file extension or use a file identification tool such as file --mime-type on the command line. Many programming languages also provide libraries to detect MIME types.
Why can one extension have multiple MIME types?
Different programs and historical usage may assign various MIME identifiers to the same file format. Listing them together helps maintain compatibility across tools.