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Showing posts from February 1, 2015

Emacs Org Mode Bable bug. For emacs lisp, session is always on

Emacs Org Mode Bable bug. For emacs lisp, session is always on.* test session; no session #+BEGIN_SRC emacs-lisp :exports both (setq x 3) #+END_SRC #+RESULTS: : 3 #+BEGIN_SRC emacs-lisp :exports both (+ 2 x) #+END_SRC #+RESULTS: : 5save the above as session-test.org, then open it, M-x org-mode. Move cursor to the elisp code block, press C-c C-c to eval. Repeat for the second block.The expected result for second block should be error of unknown variable x.

emacs: xah fly keys, harmless key maps

Global Bindings Starting With <menu> n: key binding --- ------- <menu> n RET Prefix Command <menu> n SPC Prefix Command <menu> n 0 shell-command-on-region <menu> n 1 set-input-method <menu> n 2 global-hl-line-mode <menu> n 3 whitespace-mode <menu> n 4 linum-mode <menu> n 5 visual-line-mode <menu> n 6 calendar <menu> n 7 calc <menu> n 8 shell <menu> n 9 shell-command <menu> n a text-scale-adjust <menu> n b toggle-debug-on-error <menu> n c toggle-case-fold-search <menu> n d narrow-to-page <menu> n e eshell <menu> n f Prefix Command <menu> n g toggle-frame-fullscreen <menu> n h widen <menu> n i make-frame-command <menu> n n narrow-to-region <menu> n r read-only-mode <menu> n s flyspell-buffer <menu&…

What's the Impetus that Made Lambda Calculus So Powerful?

what's lambda calculus? It's a notation, and nothing but syntax & notation.The λ-calculus is, at heart, a simple notation for functions and application. The main ideas are applying a function to an argument and forming functions by abstraction. The syntax of basic λ-calculus is quite sparse, making it an elegant, focused notation for representing functions. Functions and arguments are on a par with one another. The result is an intensional theory of functions as rules of computation, contrasting with an extensional theory of functions as sets of ordered pairs. Despite its sparse syntax, the expressiveness and flexibility of the λ-calculus make it a cornucopia of logic and mathematics. This entry develops some of the central highlights of the field and prepares the reader for further study of the subject and its applications in philosophy, linguistics, computer science, and logic.http://plato.stanford.edu/entries/lambda-calculus/and that's why, syntax is the most important …