This code is a self-invoking function (an Immediately Invoked Function...

May 18, 2025 at 11:50 AM

!function(e, t) {
    "object" == typeof exports && "undefined" != typeof module ? module.exports = t() : "function" == typeof define && define.amd ? define(t) : (e = e || self).CodeMirror = t()
} (this, (function() {
    "use strict";
    var e = navigator.userAgent,
    t = navigator.platform,
    n = /gecko\/\d/i.test(e),
    r = /MSIE \d/.test(e),
    i = /Trident\/(?:[7-9]|\d{2,})\..*rv:(\d+)/.exec(e),
    o = /Edge\/(\d+)/.exec(e),
    l = r || i || o,
    s = l && (r ? document.documentMode || 6 : +(o || i)[1]),
    a = !o && /WebKit\//.test(e),
    u = (r = a && /Qt\/\d+\.\d+/.test(e), !o && /Chrome\/(\d+)/.exec(e)),
    c = u && +u[1],
    h = /Opera\//.test(e),
    d = /Apple Computer/.test(navigator.vendor),
    f = /Mac OS X 1\d\D([8-9]|\d\d)\D/.test(e),
    p = /PhantomJS/.test(e),
    g = d && (/Mobile\/\w+/.test(e) || 2 < navigator.maxTouchPoints),
    m = /Android/.test(e),
    v = g || m || /webOS|BlackBerry|Opera Mini|Opera Mobi|IEMobile/i.test(e),
    y = g || /Mac/.test(t),
    b = /\bCrOS\b/.test(e),
    w = (i = /win/i.test(t), (o = (o = h && e.match(/Version\/(\d*\.\d*)/)) && Number(o[1])) && 15 <= o && (a = !(h = !1)), y && (r || h && (null == o || o < 12.11))),
    x = n || l && 9 <= s;
    function C(e) {
        return new RegExp("(^|\\s)" + e + "(?:$|\\s)\\s*")
    }
    var S = function(e, t) {
        var n, r = e.className; (t = C(t).exec(r)) && (n = r.slice(t.index + t[0].length), e.className = r.slice(0, t.index) + (n ? t[1] + n: ""))
    };
    function L(e) {
        for (var t = e.childNodes.length; 0 < t; --t) e.removeChild(e.firstChild);
        return e
    }
    function k(e, t) {
        return L(e).appendChild(t)
    }
    function T(e, t, n, r) {
        var i = document.createElement(e);
        if (n && (i.className = n), r && (i.style.cssText = r), "string" == typeof t) i.appendChild(document.createTextNode(t));
        else if (t) for (var o = 0; o < t.length; ++o) i.appendChild(t[o]);
        return i
    }
    function M(e, t, n, r) {
        return (e = T(e, t, n, r)).setAttribute("role", "presentation"),
        e
    }
    function N(e, t) {
        if (3 == t.nodeType && (t = t.parentNode), e.contains) return e.contains(t);
        do {
            if ((t = 11 == t.nodeType ? t.host: t) == e) return ! 0
        } while ( t = t . parentNode )
    }
    function O(e) {
        var t;
        try {
            t = e.activeElement
        } catch(n) {
            t = e.body || null
        }
        for (; t && t.shadowRoot && t.shadowRoot.activeElement;) t = t.shadowRoot.activeElement;
        return t
    }
    function A(e, t) {
        var n = e.className;
        C(t).test(n) || (e.className += (n ? " ": "") + t)
    }
    function D(e, t) {
        for (var n = e.split(" "), r = 0; r < n.length; r++) n[r] && !C(n[r]).test(t) && (t += " " + n[r]);
        return t
    }
    var W = document.createRange ?
    function(e, t, n, r) {
        var i = document.createRange();
        return i.setEnd(r || e, n),
        i.setStart(e, t),
        i
    }: function(e, t, n) {
        var r = document.body.createTextRange();
        try {
            r.moveToElementText(e.parentNode)
        } catch(e) {
            return r
        }
        return r.collapse(!0),
        r.moveEnd("character", n),
        r.moveStart("character", t),
        r
    },
    H = function(e) {
        e.select()
    };
    function F(e) {
        return e.display.wrapper.ownerDocument
    }
    function P(e) {
        return F(e).defaultView
    }
    function E(e) {
        var t = Array.prototype.slice.call(arguments, 1);
        return function() {
            return e.apply(null, t)
        }
    }
    function I(e, t, n) {
        for (var r in t = t || {},
        e) ! e.hasOwnProperty(r) || !1 === n && t.hasOwnProperty(r) || (t[r] = e[r]);
        return t
    }
    function z(e, t, n, r, i) {
        null == t && -1 == (t = e.search(/[^\s\u00a0]/)) && (t = e.length);
        for (var o = r || 0,
        l = i || 0;;) {
            var s = e.indexOf("\t", o);
            if (s < 0 || t <= s) return l + (t - o);
            l = (l += s - o) + (n - l % n),
            o = s + 1
        }
    }
    function R() {
        this.id = null,
        this.f = null,
        this.time = 0,
        this.handler = E(this.onTimeout, this)
    }
    function B(e, t) {
        for (var n = 0; n < e.length; ++n) if (e[n] == t) return n;
        return - 1
    }
    g ? H = function(e) {
        e.selectionStart = 0,
        e.selectionEnd = e.value.length
    }: l && (H = function(e) {
        try {
            e.select()
        } catch(e) {}
    }),
    R.prototype.onTimeout = function(e) {
        e.id = 0,
        e.time <= +new Date ? e.f() : setTimeout(e.handler, e.time - +new Date)
    };
    var G = {
        toString: function() {
            return "CodeMirror.Pass"
        }
    },
    U = {
        scroll: !(R.prototype.set = function(e, t) {
            this.f = t,
            t = +new Date + e,
            (!this.id || t < this.time) && (clearTimeout(this.id), this.id = setTimeout(this.handler, e), this.time = t)
        })
    },
    V = {
        origin: "*mouse"
    },
    K = {
        origin: "+move"
    };

This code is a self-invoking function (an Immediately Invoked Function Expression or IIFE) that defines and exports the CodeMirror library or object. Here's what the code does step-by-step:

Export Compatibility Logic:
- The first block decides how to export the library:
  - If the environment supports CommonJS (typeof exports and module.exports), it assigns the resulting t() function to module.exports (for Node.js or similar environments).
  - If the environment supports AMD (Asynchronous Module Definition, e.g., RequireJS), it calls define(t) to define CodeMirror as an AMD module.
  - Otherwise, it assigns the export to e.CodeMirror in the global context (e.g., in the browser's global window or self object).
Platform and Browser Detection:
- It retrieves information about the browser's user agent, platform, and device using regular expressions and feature checks (navigator.userAgent, navigator.platform, etc.).
- It determines if the browser is Gecko-based, Internet Explorer (various versions), Edge, WebKit-based, Chrome, Opera, Mac, Android, and other platforms or browsers.
- It calculates additional flags for compatibility with certain environments (e.g., touchscreen devices, specific browser versions, and quirks).
Utility Functions:
- A set of utility functions for DOM manipulation, class handling, ranges, and other tasks is defined. Examples:
  - C creates a regular expression to check for a specific CSS class.
  - S removes a class from an element's class list.
  - L clears all children from an element.
  - T creates new DOM elements, optionally including text, attributes, and styles.
  - M creates a presentation-role DOM element.
  - O retrieves the active element in a document (useful for tracking focus).
  - A and D add classes to elements or merge class names.
Caret and Selection Handling:
- Functions like W and H deal with text selection and caret placement, accounting for browser quirks.
Helper Objects:
- Objects like G, U, and others encapsulate reusable logic or constants. For instance:
  - G provides a special CodeMirror.Pass behavior (toString returns this literal).
  - U is used for scroll-related functionality.
  - V and K store predefined options or flags for common operations.
Timeout Management:
- A R constructor function manages timer-based operations and handling of repeated events. It uses the current date and time to schedule functionality.
CodeMirror Initialization:
- The function t() encapsulates all the above logic and compiles it into the main CodeMirror library object or functionality being exported.

In summary, the code initializes and configures the CodeMirror library, a widely-used text editor implemented in JavaScript. It provides tools and utilities for text editing, rendering, selection, and browser environment compatibility, wrapping everything into a module export suitable for different runtime environments (Node.js, AMD, or browsers).

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