// Switch to Mata interpreter/compiler
mata:

// Drops class object if it already exists
// mata drop a()

// Definition of HTML Tag a Mata Class
// Defines a hyperlink// Information retrieved from http://www.w3schools.com/tags/tag_a.asp
class a extends htmlglobal {

    // Define private member variables
    private:

    // Static/final variables
    static       string  scalar  opens, opene, close

    // String scalar attributes
    string               scalar          htmlcharset, htmlcoords, htmldownload, htmlhref, htmlhreflang, htmlmedia, htmlname, htmlrel, htmlrev, htmlshape, htmltarget, htmltype

    // Make class args non-static to prevent assignment of class args to all instances of class
    string               scalar          classargs

    // Define public members/methods
    public:

    // Class constructor method
    void         new()

    // Setter methods
    class        a     scalar  setClassArgs(), setCharset(), setCoords(), setDownload(), setHref(), setHreflang(), setMedia(), setName(), setRel(), setRev(), setShape(), setTarget(), setType()

    // Getter methods
    string               scalar          getOpens(), getOpene(), getClose(), print(), getClassArgs(), getCharset(), getCoords(), getDownload(), getHref(), getHreflang(), getMedia(), getName(), getRel(), getRev(), getShape(), getTarget(), getType()

} // End of class declaration

// Class constructor method declaration
void a::new() {

    // Defines the start of the opening tag for the class
    this.opens = "<a"

    // Defines the end of the opening tag for the class
    this.opene = ">"

    // Defines the closing tag for the class
    this.close = "</a>"

} // End of class constructor method definition

// Setter method for class arguments (appear between HTML tags)
class a scalar a::setClassArgs(| string scalar classarguments) {

    // Defines arguments that appear between HTML tags
    this.classargs = classarguments

    // Return a copy of the object
    return(this)

} // End of setter method for class arguments

// Not supported in HTML5.Specifies the character-set of a linked document
class a scalar a::setCharset(| string scalar methodarg) {

    // Set the attribute charset for this class
    this.htmlcharset = `" charset=""' + methodarg + `"""'

    // Return a copy of the object
    return(this)

} // End of Method charset declaration for class a

// Not supported in HTML5.Specifies the coordinates of a link
class a scalar a::setCoords(| string scalar methodarg) {

    // Set the attribute coords for this class
    this.htmlcoords = `" coords=""' + methodarg + `"""'

    // Return a copy of the object
    return(this)

} // End of Method coords declaration for class a

// Specifies that the target will be downloaded when a user clicks on the hyperlink
class a scalar a::setDownload(| string scalar methodarg) {

    // Set the attribute download for this class
    this.htmldownload = `" download=""' + methodarg + `"""'

    // Return a copy of the object
    return(this)

} // End of Method download declaration for class a

// Specifies the URL of the page the link goes to
class a scalar a::setHref(| string scalar methodarg) {

    // Set the attribute href for this class
    this.htmlhref = `" href=""' + methodarg + `"""'

    // Return a copy of the object
    return(this)

} // End of Method href declaration for class a

// Specifies the language of the linked document
class a scalar a::setHreflang(| string scalar methodarg) {

    // Set the attribute hreflang for this class
    this.htmlhreflang = `" hreflang=""' + methodarg + `"""'

    // Return a copy of the object
    return(this)

} // End of Method hreflang declaration for class a

// Specifies what media/device the linked document is optimized for
class a scalar a::setMedia(| string scalar methodarg) {

    // Set the attribute media for this class
    this.htmlmedia = `" media=""' + methodarg + `"""'

    // Return a copy of the object
    return(this)

} // End of Method media declaration for class a

// Not supported in HTML5. Use the global id attribute instead.Specifies the name of an anchor
class a scalar a::setName(| string scalar methodarg) {

    // Set the attribute name for this class
    this.htmlname = `" name=""' + methodarg + `"""'

    // Return a copy of the object
    return(this)

} // End of Method name declaration for class a

// Specifies the relationship between the current document and the linked document
class a scalar a::setRel(| string scalar methodarg) {

    // Validate argument
    if (methodarg == "alternate" | methodarg == "author" | methodarg == "bookmark" | methodarg == "help" | methodarg == "license" | methodarg == "next" | methodarg == "nofollow" | methodarg == "noreferrer" | methodarg == "prefetch" | methodarg == "prev" | methodarg == "search" | methodarg == "tag") {

        // Set the attribute value
        this.htmlrel = `" rel=""' + methodarg + `"""'

    } // End IF Block for validated argument value

    // Return a copy of the object
    return(this)

} // End of Method rel declaration for class a

// Not supported in HTML5.Specifies the relationship between the linked document and the current document
class a scalar a::setRev(| string scalar methodarg) {

    // Set the attribute rev for this class
    this.htmlrev = `" rev=""' + methodarg + `"""'

    // Return a copy of the object
    return(this)

} // End of Method rev declaration for class a

// Not supported in HTML5.Specifies the shape of a link
class a scalar a::setShape(| string scalar methodarg) {

    // Validate argument
    if (methodarg == "default" | methodarg == "rect" | methodarg == "circle" | methodarg == "poly") {

        // Set the attribute value
        this.htmlshape = `" shape=""' + methodarg + `"""'

    } // End IF Block for validated argument value

    // Return a copy of the object
    return(this)

} // End of Method shape declaration for class a

// Specifies where to open the linked document
class a scalar a::setTarget(| string scalar methodarg) {

    // Validate argument
    if (methodarg == "_blank" | methodarg == "_parent" | methodarg == "_self" | methodarg == "_top" | methodarg == "framename") {

        // Set the attribute value
        this.htmltarget = `" target=""' + methodarg + `"""'

    } // End IF Block for validated argument value

    // Return a copy of the object
    return(this)

} // End of Method target declaration for class a

// Specifies the media type of the linked document
class a scalar a::setType(| string scalar methodarg) {

    // Set the attribute type for this class
    this.htmltype = `" type=""' + methodarg + `"""'

    // Return a copy of the object
    return(this)

} // End of Method type declaration for class a

// Getter method for opening bracket
string scalar a::getOpens() {

    // Returns the opening bracket/tag w/o > character to allow attributes
    return(this.opens)

} // End of getter method for opens member of class a

// Getter method for opening bracket closing character
string scalar a::getOpene() {

    // Returns the closing character for the opening bracket
    return(this.opene)

} // End of getter method for opene member of class a

// Getter method for closing bracket
string scalar a::getClose() {

    // Returns the closing bracket/tag
    return(this.close)

} // End of getter method for close member of class a

// Getter method for class arguments
string scalar a::getClassArgs() {

    // Returns the class arguments that appear between the HTML tags
    return(this.classargs)

} // End of getter method for class arguments member of class a

// Getter method for charset member variable
string scalar a::getCharset() {

    // Returns the charset variable
    return(this.htmlcharset)

} // End of getter method for charset member of class a

// Getter method for coords member variable
string scalar a::getCoords() {

    // Returns the coords variable
    return(this.htmlcoords)

} // End of getter method for coords member of class a

// Getter method for download member variable
string scalar a::getDownload() {

    // Returns the download variable
    return(this.htmldownload)

} // End of getter method for download member of class a

// Getter method for href member variable
string scalar a::getHref() {

    // Returns the href variable
    return(this.htmlhref)

} // End of getter method for href member of class a

// Getter method for hreflang member variable
string scalar a::getHreflang() {

    // Returns the hreflang variable
    return(this.htmlhreflang)

} // End of getter method for hreflang member of class a

// Getter method for media member variable
string scalar a::getMedia() {

    // Returns the media variable
    return(this.htmlmedia)

} // End of getter method for media member of class a

// Getter method for name member variable
string scalar a::getName() {

    // Returns the name variable
    return(this.htmlname)

} // End of getter method for name member of class a

// Getter method for rel member variable
string scalar a::getRel() {

    // Returns the rel variable
    return(this.htmlrel)

} // End of getter method for rel member of class a

// Getter method for rev member variable
string scalar a::getRev() {

    // Returns the rev variable
    return(this.htmlrev)

} // End of getter method for rev member of class a

// Getter method for shape member variable
string scalar a::getShape() {

    // Returns the shape variable
    return(this.htmlshape)

} // End of getter method for shape member of class a

// Getter method for target member variable
string scalar a::getTarget() {

    // Returns the target variable
    return(this.htmltarget)

} // End of getter method for target member of class a

// Getter method for type member variable
string scalar a::getType() {

    // Returns the type variable
    return(this.htmltype)

} // End of getter method for type member of class a

// Get the HTML tag w/attributes and arguments
string scalar a::print() {

    // Create local variables to piece together return string
    string scalar open, args, close

    // Create opening string
    open = getOpens() + getCharset() + getCoords() + getDownload() + getHref() + getHreflang() + getMedia() + getName() + getRel() + getRev() + getShape() + getTarget() + getType() + globalAttrs() + getOpene()

    // Get class arguments
    args = getClassArgs()

    // Get closing tag
    close = getClose()

    // Return the complete HTML string
    return(char((10)) + subinstr(open, " >", ">") + args + close + char((10)))

} // End of print method for class a

// End of Mata session
end