API Reference

VALID_SWAP_STYLES

The set of valid swap styles for hx-swap.

getindex(elem::HTMLElement, key::Union{AbstractString, Symbol})

Get the attribute with the given key from an element.

getindex(elem::HTMLElement, i::Int)

Get the ith child of an element.

length(elem::HTMLElement)

Get the length of elem's children.

length:text::HTMLText)

Get the length of text content.

push!(elem::HTMLElement, val::HTMLElement)

Push a child onto an element.

setindex!(elem::HTMLElement, val::AbstractString, key::Union{AbstractString, Symbol})

Set the attribute with the given key on an element.

setindex!(elem::HTMLElement, val::HTMLElement, i::Integer)

Set the ith child of an element.

addclass!(elem::HTMLElement, cls::AbstractString)

Adds the class cls to elem.

applyif!(condition::Function, f!::Function, doc::HTMLDocument)

Apply f! to all elements (nested included) in doc for which condition is true.

applyif!(condition::Function, f!::Function, elem::HTMLElement)

Apply f! to all elements (nested included) in elem for which condition is true.

attributevalidation(attr::AbstractString)

Validate if attr is a valid HTML attribute name according to HTML specifications.

Attribute names must consist of one or more characters other than space characters, NULL, quotes, apostrophes, greater-than signs, forward slashes, equals signs, control characters, and any characters not defined by Unicode.

attrs(elem::HTMLElement) :: Dict{String, String}

Get the attributes of an element.

breadthfirst(node)

Return a breadth-first iterator over the tree rooted at node.

classvaluevalidation(class::AbstractString)

CSS class values validation.

findfirst(f::Function, doc::HTMLDocument) :: Union{HTMLElement, Nothing}

Find the first (PreOrderDFS) element in doc for which f is true.

findfirst(f::Function, elem::HTMLElement) :: Union{HTMLElement, Nothing}

Find the first (PreOrderDFS) element in elem for which f is true.

getattr(elem::HTMLElement, name::AbstractString, default=nothing) :: Union{String, Nothing}

Get the value of an attribute of an element or default if not present.

getbyid(doc::HTMLDocument, id::AbstractString) :: Union{HTMLElement, Nothing}

Get the element with the given id from doc.

getbyid(elem::HTMLElement, id::AbstractString) :: Union{HTMLElement, Nothing}

Get the element with the given id from elem.

hasattr(elem::HTMLElement, name::AbstractString) :: Bool

Check whether an element has an attribute.

hasclass(elem::HTMLElement, cls::AbstractString)

Returns true if elem has the class cls.

hxattr!(el::HTMLElement, attr::Union{AbstractString,Symbol}, value::AbstractString) -> HTMLElement

Set an arbitrary htmx attribute on an HTMLElement in place. The data-hx- prefix is added automatically.

hxboost!(el::HTMLElement, value::AbstractString="true") -> HTMLElement

Add an hx-boost attribute to progressively enhance links and forms to use AJAX.

hxconfirm!(el::HTMLElement, message::AbstractString) -> HTMLElement

Add an hx-confirm attribute that shows a confirm() dialog before issuing the request.

hxdelete!(el::HTMLElement, url::AbstractString) -> HTMLElement

Add an hx-delete attribute to an HTMLElement in place and return the modified element.

hxdisable!(el::HTMLElement) -> HTMLElement

Add an hx-disable attribute to prevent htmx from processing this element and its children. Useful for including untrusted user content.

hxdisabledelt!(el::HTMLElement, selector::AbstractString) -> HTMLElement

Add an hx-disabled-elt attribute to disable the specified elements during a request.

selector is a CSS selector for elements that should get the HTML disabled attribute while a request is in flight (e.g., "this", "closest button", "#submit-btn").

hxdisinherit!(el::HTMLElement, attrs::AbstractString) -> HTMLElement

Add an hx-disinherit attribute to disable automatic attribute inheritance for child nodes.

attrs can be "*" to disable all, or a space-separated list of attribute names (e.g., "hx-target hx-swap").

hxencoding!(el::HTMLElement, encoding::AbstractString="multipart/form-data") -> HTMLElement

Add an hx-encoding attribute to change the request encoding type.

Set to "multipart/form-data" for file uploads.

hxext!(el::HTMLElement, extensions::AbstractString) -> HTMLElement

Add an hx-ext attribute to enable htmx extensions for this element and its children.

Multiple extensions can be comma-separated (e.g., "response-targets,head-support"). Use "ignore:<ext-name>" to disable an inherited extension.

hxget!(el::HTMLElement, url::AbstractString) -> HTMLElement

Add an hx-get attribute to an HTMLElement in place and return the modified element.

hxheaders!(el::HTMLElement, json::AbstractString) -> HTMLElement

Add an hx-headers attribute to include additional headers with the request.

json should be a JSON-formatted string, e.g., "{"X-CSRF-Token": "abc123"}".

hxhistory!(el::HTMLElement, value::AbstractString="false") -> HTMLElement

Add an hx-history attribute. Set to "false" to prevent sensitive data on this page from being saved to the browser's history cache (localStorage).

hxhistoryelt!(el::HTMLElement) -> HTMLElement

Add an hx-history-elt attribute to mark this element as the snapshot source/target for history navigation (instead of the default body).

hxinclude!(el::HTMLElement, selector::AbstractString) -> HTMLElement

Add an hx-include attribute to include values of other elements in the request.

selector is a CSS selector indicating the elements whose values should be included.

hxindicator!(el::HTMLElement, selector::AbstractString) -> HTMLElement

Add an hx-indicator attribute specifying which element receives the htmx-request class during a request (to show a loading indicator).

hxinherit!(el::HTMLElement, attrs::AbstractString) -> HTMLElement

Add an hx-inherit attribute to explicitly enable attribute inheritance for child nodes when htmx.config.disableInheritance is set to true.

attrs can be "*" to enable all, or a space-separated list of attribute names (e.g., "hx-target hx-swap").

hxon!(el::HTMLElement, event::AbstractString, script::AbstractString) -> HTMLElement

Add an hx-on:<event> attribute to handle events with inline scripts.

The event name supports both htmx events (e.g., "htmx:before-request") and standard DOM events (e.g., "click").

Note: uses the data-hx-on:<event> form for HTML spec compliance.

hxparams!(el::HTMLElement, value::AbstractString) -> HTMLElement

Add an hx-params attribute to filter the parameters submitted with a request.

Supported values: "*" (all), "none", a comma-separated list of param names, or "not <param-list>" to exclude specific params.

hxpatch!(el::HTMLElement, url::AbstractString) -> HTMLElement

Add an hx-patch attribute to an HTMLElement in place and return the modified element.

hxpost!(el::HTMLElement, url::AbstractString) -> HTMLElement

Add an hx-post attribute to an HTMLElement in place and return the modified element.

hxpreserve!(el::HTMLElement) -> HTMLElement

Add an hx-preserve attribute to keep this element unchanged between requests. Useful for elements like video players that should maintain state across swaps.

Note: the element must have a stable id attribute.

hxprompt!(el::HTMLElement, message::AbstractString) -> HTMLElement

Add an hx-prompt attribute that shows a prompt() dialog before submitting the request. The user's response is included in the request via the HX-Prompt header.

hxpushurl!(el::HTMLElement, value::AbstractString="true") -> HTMLElement

Add an hx-push-url attribute to push the request URL into the browser location bar, creating a history entry. Pass "true", "false", or a specific URL.

hxput!(el::HTMLElement, url::AbstractString) -> HTMLElement

Add an hx-put attribute to an HTMLElement in place and return the modified element.

hxreplaceurl!(el::HTMLElement, value::AbstractString="true") -> HTMLElement

Add an hx-replace-url attribute to replace the current URL in the browser location bar without creating a new history entry. Pass "true", "false", or a specific URL.

hxrequest!(el::HTMLElement, method::Symbol, url::AbstractString) -> HTMLElement

Add an htmx request attribute to an HTMLElement in place and return the modified element.

Valid methods are :get, :post, :put, :patch, and :delete.

hxrequestconfig!(el::HTMLElement, value::AbstractString) -> HTMLElement

Add an hx-request attribute to configure various aspects of the request.

value is a JSON-like string, e.g., "timeout:3000, credentials:true" or "noHeaders:true".

hxselect!(el::HTMLElement, selector::AbstractString) -> HTMLElement

Add an hx-select attribute to select a subset of the response HTML to swap into the target.

hxselectoob!(el::HTMLElement, selectors::AbstractString) -> HTMLElement

Add an hx-select-oob attribute to pick out content for out-of-band swaps.

selectors is a comma-separated list of element IDs (e.g., "#info-details,#other-elt").

hxswap!(el::HTMLElement, style::AbstractString;
        transition::Union{Nothing,Bool}=nothing,
        swap::Union{Nothing,AbstractString}=nothing,
        settle::Union{Nothing,AbstractString}=nothing,
        ignoreTitle::Union{Nothing,Bool}=nothing,
        scroll::Union{Nothing,AbstractString}=nothing,
        show::Union{Nothing,AbstractString}=nothing,
        focusScroll::Union{Nothing,Bool}=nothing) -> HTMLElement

Add an hx-swap attribute to an HTMLElement with optional modifiers.

Arguments

• style: The swap style — one of "innerHTML" (default), "outerHTML", "afterbegin", "beforebegin", "beforeend", "afterend", "delete", "none".
• transition: Whether to use the View Transition API for this swap.
• swap: A swap delay (e.g. "100ms") between clearing old content and inserting new.
• settle: A settle delay (e.g. "100ms") between inserting new content and settling it.
• ignoreTitle: If true, any <title> found in new content will be ignored.
• scroll: "top" or "bottom" — scroll the target element to its top or bottom.
• show: "top" or "bottom" — scroll the target element's top or bottom into view.
• focusScroll: Whether the focused element should be scrolled into view.

hxswapoob!(el::HTMLElement, value::AbstractString="true") -> HTMLElement

Add an hx-swap-oob attribute to mark an element for out-of-band swapping.

The value can be "true" or any valid swap style optionally followed by a CSS selector (e.g., "innerHTML:#target").

hxsync!(el::HTMLElement, value::AbstractString) -> HTMLElement

Add an hx-sync attribute to control how requests made by different elements are synchronized.

Common values: "closest form:abort", "this:drop", "this:queue first", "this:queue last", "this:queue all", "this:replace".

hxtarget!(el::HTMLElement, selector::AbstractString) -> HTMLElement

Add an hx-target attribute to an HTMLElement.

Supported values include standard CSS selectors as well as htmx extended selectors: "this", "closest <selector>", "find <selector>", "next <selector>", "previous <selector>".

hxtrigger!(el::HTMLElement, event::AbstractString; kwargs...) -> HTMLElement

Add an hx-trigger attribute to an HTMLElement with appropriate modifiers and return the modified element.

Arguments

• el: The HTML element to add the trigger to
• event: The event name (e.g., "click", "mouseenter", "load", "revealed")
• once::Bool: Whether the trigger should only fire once
• changed::Bool: Whether the trigger should only fire if the value of the element has changed
• delay::AbstractString: A time interval (e.g., "1s") to wait before issuing the request
• throttle::AbstractString: A time interval (e.g., "1s") to throttle requests
• from::AbstractString: A CSS selector to listen for the event on a different element
• target::AbstractString: A CSS selector to filter the trigger to elements matching the selector
• consume::Bool: Whether the event should be consumed (not propagated to parent elements)
• queue::AbstractString: Queue strategy when a request is in flight ("first", "last", "all", "none")
• filter::AbstractString: A JavaScript expression to filter when the trigger fires (without brackets)

hxvalidate!(el::HTMLElement) -> HTMLElement

Add an hx-validate attribute to force elements to validate themselves before a request. This integrates with the HTML5 Validation API.

hxvals!(el::HTMLElement, json::AbstractString) -> HTMLElement

Add an hx-vals attribute to include additional values with the request.

json should be a JSON-formatted string of name-value pairs, e.g., "{"myVal": "My Value"}".

intersect_trigger(el::HTMLElement; 
                 root::Union{Nothing,AbstractString}=nothing,
                 threshold::Union{Nothing,Real}=nothing,
                 once::Bool=true) -> HTMLElement

Add an 'intersect' trigger to an element (fires when element intersects the viewport).

Arguments

• root: A CSS selector of the root element for intersection
• threshold: A floating point between 0.0 and 1.0 indicating the amount of intersection needed

load_trigger(el::HTMLElement; delay::Union{Nothing,AbstractString}=nothing) -> HTMLElement

Add a 'load' trigger to an element, optionally with a delay.

Examples

# Trigger on load
load_trigger(el)

# Trigger on load with delay
load_trigger(el; delay="1s")

parsehtml_snippet(input::AbstractString; preserve_whitespace=false, preserve_template=false)

Parse an HTML snippet into an HTMLElement. This is useful for parsing a snippet of HTML that is not a complete document, such as a <div> tag.

Note: this function is not as robust as parsehtml and may not work for all inputs. Also, the assumption is that the tag is intended to part of the <body> tag.

For scenarios where the snippet is composed from multiple sequential tags, the output will be wrapped in a <div> tag.

poll_trigger(el::HTMLElement, interval::AbstractString) -> HTMLElement

Add a polling trigger to an element.

Arguments

• interval: The polling interval (e.g., "2s", "500ms")

Examples

# Poll every 2 seconds
poll_trigger(el, "2s")

postorder(node)

Return a post-order depth-first iterator over the tree rooted at node.

preorder(node)

Return a pre-order depth-first iterator over the tree rooted at node.

removeclass!(elem::HTMLElement, cls::AbstractString)

Removes the class cls from elem.

revealed_trigger(el::HTMLElement; once::Bool=true) -> HTMLElement

Add a 'revealed' trigger to an element (fires when element scrolls into view). By default, this only triggers once.

setattrs!(elem::HTMLElement, name::AbstractString, value::AbstractString)

Set the attributes of an element.

tag(elem::HTMLElement)

Get the tag of an element.

text(el::HTMLElement) :: AbstractString

Get the text of an element.

text(t::HTMLText) :: AbstractString

Get the text of a text element.

validate(::Val{:attr}, value::AbstractString)

Validate HTML attribute names.

validate(::Val{:attr}, value::AbstractString)

Validate HTML attribute names.

validate(::Val{:class}, value::AbstractString)

Validate CSS class names.

validate(::Val{:class}, values::Vector{<:AbstractString})

Validate CSS class names.

@validate type value

Validate HTML elements based on their type using compile-time dispatch.

Arguments

• type: Symbol indicating what to validate (:attr for attribute names, :class for class names)
• value: The string(s) value to validate

Examples

@validate :attr "class"  # Validates an attribute name
@validate :attr ["id", "data-value"]  # Validates multiple attribute names
@validate :class "my-class"  # Validates a class name
@validate :class ["class1", "class2"]  # Validates multiple class names

Returns

Returns true if validation passes, otherwise throws an error.