# Halon Scripting Language

> Halon Scripting Language 6.12-stable documentation

## Pages

- [Halon Scripting Language](index.html.md): Halon is a fast, flexible and powerful email infrastructure software; designed for demanding uses such as large-scale email services.
- [About](about.html.md): Halon’s scripting language is a domain-specific language (DSL) for Halon’s email platform.
- [Introduction](introduction.html.md): This language reference manual will not cover the basics of programming, instead it’s a reference manual for the language.
- [Data types and literals](literals.html.md): HSL has multiple data types; strings, booleans, numbers, arrays (which also works as an ordered map to store key-value pairs, similar to PHP’s array), objects (created by classes) and functions (both anonymous functions and named function pointers).
- [Operators](operators.html.md): Operators are used with one or more values (or expressions) which yields another value (so that the operator itself becomes an expression).
- [Control structures](structures.html.md): A few language constructs are available in HSL in order to control program flow.
- [Standard library](functions.html.md): Functions which are documented in this chapter are considered core functions hence are available in all contexts.
- [SMTP server](smtpserver.html.md): There are multiple extensions to the language, which provides context specific variables and functions.
- [Connect](connect.html.md): This script is executed before the SMTP banner is sent.
- [Proxy](proxy.html.md): This advanced and powerful script can be executed before an SMTP command is sent to the internal state machine of the SMTP server (hence before the command is processed by the SMTP server).
- [HELO](helo.html.md): This script is executed on HELO and EHLO.
- [AUTH](auth.html.md): The AUTH script allows trusted SMTP clients to authenticate.
- [MAIL FROM](mailfrom.html.md): The MAIL FROM script allows verification of the sender.
- [RCPT TO](rcptto.html.md): The RCPT TO script allows verification of recipients.
- [End-of-DATA](eod.html.md): The end-of-DATA script is executed once, when the message is fully received (but not yet accepted).
- [Disconnect](disconnect.html.md): This script is executed when the client has disconnected.
- [SMTP queue](smtpqueue.html.md): The smtpd process implements the pre- and post-delivery contexts.
- [Pre-delivery](predelivery.html.md): The pre-delivery script is executed just before an email is being put into the active queue (for delivery as soon as the active queue policies allow).
- [Post-delivery](postdelivery.html.md): The post-delivery script is executed after a delivery attempt or when a message is deleted or bounced from the queue.
- [Integrations](integrations.html.md): The following integrations are available in our Halon Extras repository on Github.

## Optional

- [llms-full.txt](llms-full.txt): Complete documentation in a single file.