| Safe Haskell | None |
|---|---|
| Language | Haskell98 |
Text.Blaze
Contents
Description
BlazeMarkup is a markup combinator library. It provides a way to embed markup languages like HTML and SVG in Haskell in an efficient and convenient way, with a light-weight syntax.
To use the library, one needs to import a set of combinators. For example, you can use HTML 4 Strict from BlazeHtml package.
{-# LANGUAGE OverloadedStrings #-}
import Prelude hiding (head, id, div)
import Text.Blaze.Html4.Strict hiding (map)
import Text.Blaze.Html4.Strict.Attributes hiding (title)To render the page later on, you need a so called Renderer. The recommended renderer is an UTF-8 renderer which produces a lazy bytestring.
import Text.Blaze.Renderer.Utf8 (renderMarkup)
Now, you can describe pages using the imported combinators.
page1 :: Markup
page1 = html $ do
head $ do
title "Introduction page."
link ! rel "stylesheet" ! type_ "text/css" ! href "screen.css"
body $ do
div ! id "header" $ "Syntax"
p "This is an example of BlazeMarkup syntax."
ul $ mapM_ (li . toMarkup . show) [1, 2, 3]The resulting HTML can now be extracted using:
renderMarkup page1
- type Markup = MarkupM ()
- data Tag
- data Attribute
- data AttributeValue
- dataAttribute :: Tag -> AttributeValue -> Attribute
- customAttribute :: Tag -> AttributeValue -> Attribute
- class ToMarkup a where
- text :: Text -> Markup
- preEscapedText :: Text -> Markup
- lazyText :: Text -> Markup
- preEscapedLazyText :: Text -> Markup
- string :: String -> Markup
- preEscapedString :: String -> Markup
- unsafeByteString :: ByteString -> Markup
- unsafeLazyByteString :: ByteString -> Markup
- textComment :: Text -> Markup
- lazyTextComment :: Text -> Markup
- stringComment :: String -> Markup
- unsafeByteStringComment :: ByteString -> Markup
- unsafeLazyByteStringComment :: ByteString -> Markup
- textTag :: Text -> Tag
- stringTag :: String -> Tag
- class ToValue a where
- textValue :: Text -> AttributeValue
- preEscapedTextValue :: Text -> AttributeValue
- lazyTextValue :: Text -> AttributeValue
- preEscapedLazyTextValue :: Text -> AttributeValue
- stringValue :: String -> AttributeValue
- preEscapedStringValue :: String -> AttributeValue
- unsafeByteStringValue :: ByteString -> AttributeValue
- unsafeLazyByteStringValue :: ByteString -> AttributeValue
- (!) :: Attributable h => h -> Attribute -> h
- (!?) :: Attributable h => h -> (Bool, Attribute) -> h
- contents :: MarkupM a -> MarkupM a
Important types.
Type for an HTML tag. This can be seen as an internal string type used by BlazeMarkup.
Creating attributes.
Arguments
| :: Tag | Name of the attribute. |
| -> AttributeValue | Value for the attribute. |
| -> Attribute | Resulting HTML attribute. |
From HTML 5 onwards, the user is able to specify custom data attributes.
An example:
<p data-foo="bar">Hello.</p>
We support this in BlazeMarkup using this function. The above fragment could be described using BlazeMarkup with:
p ! dataAttribute "foo" "bar" $ "Hello."
Arguments
| :: Tag | Name of the attribute |
| -> AttributeValue | Value for the attribute |
| -> Attribute | Resulting HTML attribtue |
Create a custom attribute. This is not specified in the HTML spec, but some JavaScript libraries rely on it.
An example:
<select dojoType="select">foo</select>
Can be produced using:
select ! customAttribute "dojoType" "select" $ "foo"
Converting values to Markup.
class ToMarkup a where Source #
Class allowing us to use a single function for Markup values
Minimal complete definition
Methods
toMarkup :: a -> Markup Source #
Convert a value to Markup.
preEscapedToMarkup :: a -> Markup Source #
Convert a value to Markup without escaping
Instances
Render text. Functions like these can be used to supply content in HTML.
Render text without escaping.
A variant of preEscapedText for lazy Text
Create an HTML snippet from a String.
Create an HTML snippet from a String without escaping
Arguments
| :: ByteString | Value to insert. |
| -> Markup | Resulting HTML fragment. |
Insert a ByteString. This is an unsafe operation:
- The
ByteStringcould have the wrong encoding. - The
ByteStringmight contain illegal HTML characters (no escaping is done).
Arguments
| :: ByteString | Value to insert |
| -> Markup | Resulting HTML fragment |
Insert a lazy ByteString. See unsafeByteString for reasons why this
is an unsafe operation.
Comments
textComment :: Text -> Markup Source #
Create a comment from a Text value.
The text should not contain "--".
This is not checked by the library.
lazyTextComment :: Text -> Markup Source #
Create a comment from a Text value.
The text should not contain "--".
This is not checked by the library.
stringComment :: String -> Markup Source #
Create a comment from a String value.
The text should not contain "--".
This is not checked by the library.
unsafeByteStringComment :: ByteString -> Markup Source #
Create a comment from a ByteString value.
The text should not contain "--".
This is not checked by the library.
unsafeLazyByteStringComment :: ByteString -> Markup Source #
Create a comment from a ByteString value.
The text should not contain "--".
This is not checked by the library.
Creating tags.
Converting values to attribute values.
class ToValue a where Source #
Class allowing us to use a single function for attribute values
Minimal complete definition
Methods
toValue :: a -> AttributeValue Source #
Convert a value to an attribute value
preEscapedToValue :: a -> AttributeValue Source #
Convert a value to an attribute value without escaping
Instances
Arguments
| :: Text | The actual value. |
| -> AttributeValue | Resulting attribute value. |
Render an attribute value from Text.
Arguments
| :: Text | The actual value |
| -> AttributeValue | Resulting attribute value |
Render an attribute value from Text without escaping.
Arguments
| :: Text | The actual value |
| -> AttributeValue | Resulting attribute value |
preEscapedLazyTextValue Source #
Arguments
| :: Text | The actual value |
| -> AttributeValue | Resulting attribute value |
A variant of preEscapedTextValue for lazy Text
stringValue :: String -> AttributeValue Source #
Create an attribute value from a String.
preEscapedStringValue :: String -> AttributeValue Source #
Create an attribute value from a String without escaping.
unsafeByteStringValue Source #
Arguments
| :: ByteString | ByteString value |
| -> AttributeValue | Resulting attribute value |
Create an attribute value from a ByteString. See unsafeByteString
for reasons why this might not be a good idea.
unsafeLazyByteStringValue Source #
Arguments
| :: ByteString | ByteString value |
| -> AttributeValue | Resulting attribute value |
Create an attribute value from a lazy ByteString. See
unsafeByteString for reasons why this might not be a good idea.
Setting attributes
(!) :: Attributable h => h -> Attribute -> h Source #
Apply an attribute to an element.
Example:
img ! src "foo.png"
Result:
<img src="foo.png" />
This can be used on nested elements as well.
Example:
p ! style "float: right" $ "Hello!"
Result:
<p style="float: right">Hello!</p>
(!?) :: Attributable h => h -> (Bool, Attribute) -> h Source #
Shorthand for setting an attribute depending on a conditional.
Example:
p !? (isBig, A.class "big") $ "Hello"
Gives the same result as:
(if isBig then p ! A.class "big" else p) "Hello"