Message Composition with MML (MIME Meta Language)

Himalaya uses MML for composing emails. MML is a simple XML-based syntax that compiles to MIME messages.

Basic Message Structure

An email message is a list of headers followed by a body, separated by a blank line:

`

From: sender@example.com

To: recipient@example.com

Subject: Hello World

This is the message body.

`

Headers

Common headers:

• - From: Sender address
• - To: Primary recipient(s)
• - Cc: Carbon copy recipients
• - Bcc: Blind carbon copy recipients
• - Subject: Message subject
• - Reply-To: Address for replies (if different from From)
• - In-Reply-To: Message ID being replied to

Address Formats

`

To: user@example.com

To: John Doe

To: "John Doe"

To: user1@example.com, user2@example.com, "Jane"

`

Plain Text Body

Simple plain text email:

`

From: alice@localhost

To: bob@localhost

Subject: Plain Text Example

Hello, this is a plain text email.

No special formatting needed.

Best,

Alice

`

MML for Rich Emails

Multipart Messages

Alternative text/html parts:

`

From: alice@localhost

To: bob@localhost

Subject: Multipart Example

<#multipart type=alternative>

This is the plain text version.

<#part type=text/html>

This is the HTML version

<#/multipart>

`

Attachments

Attach a file:

`

From: alice@localhost

To: bob@localhost

Subject: With Attachment

Here is the document you requested.

<#part filename=/path/to/document.pdf><#/part>

`

Attachment with custom name:

`

<#part filename=/path/to/file.pdf name=report.pdf><#/part>

`

Multiple attachments:

`

<#part filename=/path/to/doc1.pdf><#/part>

<#part filename=/path/to/doc2.pdf><#/part>

`

Inline Images

Embed an image inline:

`

From: alice@localhost

To: bob@localhost

Subject: Inline Image

<#multipart type=related>

<#part type=text/html>

Check out this image:



<#part disposition=inline id=image1 filename=/path/to/image.png><#/part>

<#/multipart>

`

Mixed Content (Text + Attachments)

`

From: alice@localhost

To: bob@localhost

Subject: Mixed Content

<#multipart type=mixed>

<#part type=text/plain>

Please find the attached files.

Best,

Alice

<#part filename=/path/to/file1.pdf><#/part>

<#part filename=/path/to/file2.zip><#/part>

<#/multipart>

`

MML Tag Reference

<#multipart>

Groups multiple parts together.

• - type=alternative: Different representations of same content
• - type=mixed: Independent parts (text + attachments)
• - type=related: Parts that reference each other (HTML + images)

<#part>

Defines a message part.

• - type=: Content type (e.g., text/html, application/pdf)
• - filename=: File to attach
• - name=: Display name for attachment
• - disposition=inline: Display inline instead of as attachment
• - id=: Content ID for referencing in HTML

Composing from CLI

Interactive compose

Opens your $EDITOR:

`bash

himalaya message write

`

Reply (opens editor with quoted message)

`bash

himalaya message reply 42

himalaya message reply 42 --all # reply-all

`

Forward

`bash

himalaya message forward 42

`

Send from stdin

`bash

cat message.txt | himalaya template send

`

Prefill headers from CLI

`bash

himalaya message write \

-H "To:recipient@example.com" \

-H "Subject:Quick Message" \

"Message body here"

`

Tips

• - The editor opens with a template; fill in headers and body.
• - Save and exit the editor to send; exit without saving to cancel.
• - MML parts are compiled to proper MIME when sending.
• - Use himalaya message export --full to inspect the raw MIME structure of received emails.