Selection = function(session) {
    this.session = session;
    this.doc = session.getDocument();

    this.clearSelection();
    this.lead = this.selectionLead = this.doc.createAnchor(0, 0);
    this.anchor = this.selectionAnchor = this.doc.createAnchor(0, 0);

    var self = this;
    this.lead.on("change", function(e) {
        self._emit("changeCursor");
        if (!self.$isEmpty)
            self._emit("changeSelection");
        if (!self.$keepDesiredColumnOnChange && e.old.column != e.value.column)
            self.$desiredColumn = null;
    });

    this.selectionAnchor.on("change", function() {
        if (!self.$isEmpty)
            self._emit("changeSelection");
    });
}
new Selection(session)
- session (EditSession): The session to use

Creates a new `Selection` object.