Notes/libraries/codemirror/mode/r/r.js

// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: https://codemirror.net/LICENSE

(function(mod) {
  if (typeof exports == "object" && typeof module == "object") // CommonJS
    mod(require("../../lib/codemirror"));
  else if (typeof define == "function" && define.amd) // AMD
    define(["../../lib/codemirror"], mod);
  else // Plain browser env
    mod(CodeMirror);
})(function(CodeMirror) {
"use strict";

CodeMirror.registerHelper("wordChars", "r", /[\w.]/);

CodeMirror.defineMode("r", function(config) {
  function wordObj(words) {
    var res = {};
    for (var i = 0; i < words.length; ++i) res[words[i]] = true;
    return res;
  }
  var commonAtoms = ["NULL", "NA", "Inf", "NaN", "NA_integer_", "NA_real_", "NA_complex_", "NA_character_", "TRUE", "FALSE"];
  var commonBuiltins = ["list", "quote", "bquote", "eval", "return", "call", "parse", "deparse"];
  var commonKeywords = ["if", "else", "repeat", "while", "function", "for", "in", "next", "break"];
  var commonBlockKeywords = ["if", "else", "repeat", "while", "function", "for"];

  CodeMirror.registerHelper("hintWords", "r", commonAtoms.concat(commonBuiltins, commonKeywords));

  var atoms = wordObj(commonAtoms);
  var builtins = wordObj(commonBuiltins);
  var keywords = wordObj(commonKeywords);
  var blockkeywords = wordObj(commonBlockKeywords);
  var opChars = /[+\-*\/^<>=!&|~$:]/;
  var curPunc;

  function tokenBase(stream, state) {
    curPunc = null;
    var ch = stream.next();
    if (ch == "#") {
      stream.skipToEnd();
      return "comment";
    } else if (ch == "0" && stream.eat("x")) {
      stream.eatWhile(/[\da-f]/i);
      return "number";
    } else if (ch == "." && stream.eat(/\d/)) {
      stream.match(/\d*(?:e[+\-]?\d+)?/);
      return "number";
    } else if (/\d/.test(ch)) {
      stream.match(/\d*(?:\.\d+)?(?:e[+\-]\d+)?L?/);
      return "number";
    } else if (ch == "'" || ch == '"') {
      state.tokenize = tokenString(ch);
      return "string";
    } else if (ch == "`") {
      stream.match(/[^`]+`/);
      return "variable-3";
    } else if (ch == "." && stream.match(/.[.\d]+/)) {
      return "keyword";
    } else if (/[\w\.]/.test(ch) && ch != "_") {
      stream.eatWhile(/[\w\.]/);
      var word = stream.current();
      if (atoms.propertyIsEnumerable(word)) return "atom";
      if (keywords.propertyIsEnumerable(word)) {
        // Block keywords start new blocks, except 'else if', which only starts
        // one new block for the 'if', no block for the 'else'.
        if (blockkeywords.propertyIsEnumerable(word) &&
            !stream.match(/\s*if(\s+|$)/, false))
          curPunc = "block";
        return "keyword";
      }
      if (builtins.propertyIsEnumerable(word)) return "builtin";
      return "variable";
    } else if (ch == "%") {
      if (stream.skipTo("%")) stream.next();
      return "operator variable-2";
    } else if (
        (ch == "<" && stream.eat("-")) ||
        (ch == "<" && stream.match("<-")) ||
        (ch == "-" && stream.match(/>>?/))
      ) {
      return "operator arrow";
    } else if (ch == "=" && state.ctx.argList) {
      return "arg-is";
    } else if (opChars.test(ch)) {
      if (ch == "$") return "operator dollar";
      stream.eatWhile(opChars);
      return "operator";
    } else if (/[\(\){}\[\];]/.test(ch)) {
      curPunc = ch;
      if (ch == ";") return "semi";
      return null;
    } else {
      return null;
    }
  }

  function tokenString(quote) {
    return function(stream, state) {
      if (stream.eat("\\")) {
        var ch = stream.next();
        if (ch == "x") stream.match(/^[a-f0-9]{2}/i);
        else if ((ch == "u" || ch == "U") && stream.eat("{") && stream.skipTo("}")) stream.next();
        else if (ch == "u") stream.match(/^[a-f0-9]{4}/i);
        else if (ch == "U") stream.match(/^[a-f0-9]{8}/i);
        else if (/[0-7]/.test(ch)) stream.match(/^[0-7]{1,2}/);
        return "string-2";
      } else {
        var next;
        while ((next = stream.next()) != null) {
          if (next == quote) { state.tokenize = tokenBase; break; }
          if (next == "\\") { stream.backUp(1); break; }
        }
        return "string";
      }
    };
  }

  var ALIGN_YES = 1, ALIGN_NO = 2, BRACELESS = 4

  function push(state, type, stream) {
    state.ctx = {type: type,
                 indent: state.indent,
                 flags: 0,
                 column: stream.column(),
                 prev: state.ctx};
  }
  function setFlag(state, flag) {
    var ctx = state.ctx
    state.ctx = {type: ctx.type,
                 indent: ctx.indent,
                 flags: ctx.flags | flag,
                 column: ctx.column,
                 prev: ctx.prev}
  }
  function pop(state) {
    state.indent = state.ctx.indent;
    state.ctx = state.ctx.prev;
  }

  return {
    startState: function() {
      return {tokenize: tokenBase,
              ctx: {type: "top",
                    indent: -config.indentUnit,
                    flags: ALIGN_NO},
              indent: 0,
              afterIdent: false};
    },

    token: function(stream, state) {
      if (stream.sol()) {
        if ((state.ctx.flags & 3) == 0) state.ctx.flags |= ALIGN_NO
        if (state.ctx.flags & BRACELESS) pop(state)
        state.indent = stream.indentation();
      }
      if (stream.eatSpace()) return null;
      var style = state.tokenize(stream, state);
      if (style != "comment" && (state.ctx.flags & ALIGN_NO) == 0) setFlag(state, ALIGN_YES)

      if ((curPunc == ";" || curPunc == "{" || curPunc == "}") && state.ctx.type == "block") pop(state);
      if (curPunc == "{") push(state, "}", stream);
      else if (curPunc == "(") {
        push(state, ")", stream);
        if (state.afterIdent) state.ctx.argList = true;
      }
      else if (curPunc == "[") push(state, "]", stream);
      else if (curPunc == "block") push(state, "block", stream);
      else if (curPunc == state.ctx.type) pop(state);
      else if (state.ctx.type == "block" && style != "comment") setFlag(state, BRACELESS)
      state.afterIdent = style == "variable" || style == "keyword";
      return style;
    },

    indent: function(state, textAfter) {
      if (state.tokenize != tokenBase) return 0;
      var firstChar = textAfter && textAfter.charAt(0), ctx = state.ctx,
          closing = firstChar == ctx.type;
      if (ctx.flags & BRACELESS) ctx = ctx.prev
      if (ctx.type == "block") return ctx.indent + (firstChar == "{" ? 0 : config.indentUnit);
      else if (ctx.flags & ALIGN_YES) return ctx.column + (closing ? 0 : 1);
      else return ctx.indent + (closing ? 0 : config.indentUnit);
    },

    lineComment: "#"
  };
});

CodeMirror.defineMIME("text/x-rsrc", "r");

});