Editing Curl (programming language) (section)

==Syntax==
A simple Curl applet for a [["Hello, World!" program]] might be:

<syntaxhighlight lang="text">
 {Curl 7.0, 8.0 applet}
 {text
    color = "blue",
    font-size = 16pt,
    Hello World}
</syntaxhighlight>

This code will run if the user has at least one of the Curl versions 7.0 or 8.0 installed.

Curl provides both [[Macro (computer science)|macro]]s and text-procedures in addition to anonymous procedures and named methods.
An alternative using the text-procedure ''paragraph'' would be:

<syntaxhighlight lang="text">
 {paragraph
    paragraph-left-indent=0.5in,
    {text color = "red", font-size = 12pt,
      Hello}
    {text color = "green", font-size = 12pt,
      World}}
</syntaxhighlight>

Recently this style of layout has been adopted by "builders" in the [[Groovy (programming language)|Groovy]] language for the [[Java virtual machine]] (JVM), but is also familiar to users of CSS or [[Tcl]]/[[Tk (software)|Tk]]. Most features for web applications now implemented through combinations of JavaScript libraries + HTML + CSS  are already found within the Curl language, including features usually associated with [[Prototype JavaScript Framework|Prototype]] + [[script.aculo.us]] such as accordion panes.

Curl sets callbacks in the manner also adopted by Groovy:

<syntaxhighlight lang="text">
 {CommandButton width=100pt,
    height = 50pt,
    label = {center {bold Invokes an event handler when clicked}},
    control-color = "orange",
    || Attach the following event handler to this CommandButton
    {on Action do
        {popup-message
            title = "Your Message",
            "This is a user message dialog."
        }
    }}
</syntaxhighlight>

Curl comments use the vertical bar in several variations.  The simplest is as follows:

<syntaxhighlight lang="text">
 {text A comment can be on a line by itself,
 || A comment on a line by itself
 or it can be at the end || A comment on the same line as code
 of a line.}
</syntaxhighlight>