stream7

 literally always have to look up the meaning of :limit in migrations when it comes to integer values. Here's an overview. Now let's memorise it (oh, this works for MySQL, other databases may work differently):

:limit	    Numeric Type	Column Size	Max value
1	     tinyint	         1 byte	          127
2	     smallint	         2 bytes	32767
3	     mediumint	         3 byte	        8388607
nil, 4, 11    int(11)	         4 byte	       2147483647
5..8	      bigint	         8 byte	     9223372036854775807

Note: by default MySQL uses signed integers and Rails has no way (that I know of) to change this behaviour. Subsequently, the max. values noted are for signed integers.

twfarland

;; 12.4 Rearranging words

;; a 'word' is either 
;; 1 - empty, or 
;; 2 - (cons a w) where a is a symbol 
;; ('a, 'b,..., 'z) and w is a word

;; examples:
(define noword empty)
(define red (cons 'r (cons 'e (cons 'd empty))))

zhengjia

=Navigating=
    visit('/projects')
    visit(post_comments_path(post))

=Clicking links and buttons=
    click_link('id-of-link')
    click_link('Link Text')
    click_button('Save')
    click('Link Text') # Click either a link or a button
    click('Button Value')