What is MIME type "application/x-standardml"?

A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.

application/x-standardml marks files that contain source code in the Standard ML programming language. It tells text editors, compilers, and web servers how to treat the file content.

Files using this MIME type typically carry the SML extension.

Enables proper syntax highlighting in code editors.
Helps compilers and interpreters correctly process Standard ML source code.
Assists web servers in serving the file with the appropriate handling rules.

Technical Note: The use of the x- prefix indicates that this is a non-standard, experimental, or custom MIME type.

For more on the language, see Standard ML on Wikipedia.

Associated file extensions

.sml

Usage Examples

HTTP Header

When serving content with this MIME type, set the Content-Type header:


    Content-Type: application/x-standardml

HTML

In HTML, you can specify the MIME type in various elements:


    <a href="file.dat" type="application/x-standardml">Download file</a>

Server-side (Node.js)

Setting the Content-Type header in Node.js:


    const http = require('http');    
    
    http.createServer((req, res) => {    
      res.setHeader('Content-Type', 'application/x-standardml');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.sml

FAQs

What kind of content does application/x-standardml represent?

The MIME type application/x-standardml represents source code written in Standard ML (SML), a general-purpose, modular, functional programming language. These files are typically plain text documents containing logic and algorithms intended for compilation or interpretation.

How do I open a file with the .sml extension?

Since .sml files are plain text, you can view and edit them using any code editor like Visual Studio Code, Emacs, or Notepad++. To run the code, you will need a Standard ML implementation such as SML/NJ (Standard ML of New Jersey) or MLton.

How do I configure Apache to serve .sml files correctly?

To ensure your Apache server sends the correct headers for Standard ML files, add the following line to your .htaccess file or main configuration: AddType application/x-standardml .sml. This ensures browsers and clients identify the file type accurately.

Can web browsers execute application/x-standardml files?

No, web browsers cannot execute Standard ML code natively. If a browser navigates to a file served as application/x-standardml, it will usually trigger a download prompt. To display the code in the browser instead, the server might need to serve it as text/plain.

What does the 'x-' prefix mean in this MIME type?

The x- prefix indicates that application/x-standardml is a non-standard or experimental subtype not officially registered with the IANA. While widely recognized by SML tools, it is a convention rather than a strict web standard.

Are there alternative MIME types for Standard ML files?

Yes, because .sml files are text-based, they are frequently identified as text/plain to ensure maximum compatibility. You may also encounter text/x-standardml or text/x-sml, which classify the content as text rather than a generic application binary.

Is it safe to download files with this MIME type?

Files with the application/x-standardml type are generally just text source code and are safe to view. However, you should never compile or execute code from untrusted sources, as running malicious scripts can compromise your system.

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 are multiple MIME types listed for one extension?

Different applications and historical conventions may use alternative MIME identifiers for the same kind of file. Showing them all helps ensure compatibility across systems.