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How does a while loop work in Emacs Lisp?
Emacs Lisp has two primary ways to cause an expression, or a series of expressions, to be evaluated repeatedly: one uses a while loop, and the other uses recursion. Repetition can be very valuable. For example, to move forward four sentences, you need only write a program that will move forward one sentence and then repeat the process four times.
How do you evaluate Elisp code in Emacs?
To evaluate elisp code, for example, type (+ 3 4), then move your cursor to after the closing parenthesis, then call eval-last-sexp 【 Ctrl + x Ctrl + e 】. Emacs will evaluate the lisp expression to the left of the cursor.
What happens to a while expression in Lisp?
In a while expression, if the value returned by evaluating the first argument is false, the Lisp interpreter skips the rest of the expression (the body of the expression) and does not evaluate it.
Where can I find edebug in Emacs Lisp?
Edebug is described in section `Edebug’ in The GNU Emacs Lisp Reference Manual . Here is a bugged function definition for triangle-recursively . See section Recursion in Place of a Counter , for a review of it. This example is presented without indentation to the left of the defun, as explained below.
Can you tell Emacs to re-start after terminating?
As far as I know you cannot tell Emacs to re-start after terminating, but you can set the exit code so that the process that started Emacs in the first place can detect that you want to re-start. For example, this shell script re-starts Emacs if it exited with the code 123.
What does recursion mean in Lisp special form?
Recursion: Causing a function to call itself. The while special form tests whether the value returned by evaluating its first argument is true or false. This is similar to what the Lisp interpreter does with an if; what the interpreter does next, however, is different.