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GNU Info (elisp)Symbol FormsSymbol Forms ------------ When a symbol is evaluated, it is treated as a variable. The result is the variable's value, if it has one. If it has none (if its value cell is void), an error is signaled. For more information on the use of variables, see Note: Variables. In the following example, we set the value of a symbol with `setq'. Then we evaluate the symbol, and get back the value that `setq' stored. (setq a 123) => 123 (eval 'a) => 123 a => 123 The symbols `nil' and `t' are treated specially, so that the value of `nil' is always `nil', and the value of `t' is always `t'; you cannot set or bind them to any other values. Thus, these two symbols act like self-evaluating forms, even though `eval' treats them like any other symbol. A symbol whose name starts with `:' also self-evaluates in the same way; likewise, its value ordinarily cannot be changed. Note: Constant Variables. automatically generated by info2www version 1.2.2.9 |