Function parseAssignment

src/expression/parse.js:697–742

* Assignment of a function or variable, * - can be a variable like 'a=2.3' * - or a updating an existing variable like 'matrix(2,3:5)=[6,7,8]' * - defining a function like 'f(x) = x^2' * @return {Node} node * @private

(state)

   * @private
   */
  function parseAssignment (state) {
    let name, args, value, valid

    const node = parseConditional(state)

    if (state.token === '=') {
      if (isSymbolNode(node)) {
        // parse a variable assignment like 'a = 2/3'
        name = node.name
        getTokenSkipNewline(state)
        value = parseAssignment(state)
        return new AssignmentNode(new SymbolNode(name), value)
      } else if (isAccessorNode(node)) {
        // parse a matrix subset assignment like 'A[1,2] = 4'
        if (node.optionalChaining) {
          throw createSyntaxError(state, 'Cannot assign to optional chain')
        }
        getTokenSkipNewline(state)
        value = parseAssignment(state)
        return new AssignmentNode(node.object, node.index, value)
      } else if (isFunctionNode(node) && isSymbolNode(node.fn)) {
        // parse function assignment like 'f(x) = x^2'
        valid = true
        args = []

        name = node.name
        node.args.forEach(function (arg, index) {
          if (isSymbolNode(arg)) {
            args[index] = arg.name
          } else {
            valid = false
          }
        })

        if (valid) {
          getTokenSkipNewline(state)
          value = parseAssignment(state)
          return new FunctionAssignmentNode(name, args, value)
        }
      }

      throw createSyntaxError(state, 'Invalid left hand side of assignment operator =')
    }

    return node
  }

  /**
   * conditional operation