On Fri, Apr 29, 2011 at 1:08 PM, Raul Miller <[email protected]> wrote:
> subst6=: (8 u: [: u:@dfh 2 }. ]) ::] ^:(6&=@# *. ('\' = {.) *. 'uU'
> e.~ {.@}.)&.>
Watch out for split lines.
Here's that one again, with some whitespace removed to hopefully help
the code escape mutilation:
NB. backslash evaluator
subst2=:(_2<\'\"\\\/\b\f\n\r\t')&(i.{(34 92 47 8 12 10 13 9{&.><a.),])"0
hexchars=. 'ABCDEF0123456789abcdef'
dfh=: 16 #. 16 | _6 + hexchars i. ]
subst6=:(8 u:[:u:@dfh 2}.]) ::]^:(6&=@#*.('\'={.)*.'uU'e.~{.@}.)&.>
splitbs=: (0;(0 10#:10*".;._2]0 :0);(a.e.hexchars,'Uu')+2*a.='\')&;:
1.1 1.1 2.1 NB. state 0 -- start
1.0 1.0 2.2 NB. state 1 -- ordinary characters
3.0 4.0 3.0 NB. state 2 -- \
1.2 1.2 2.2 NB. state 3 -- \n or \u0000
1.2 5.0 1.2 NB. state 4 -- \u
1.2 6.0 1.2 NB. state 5 -- \u0
1.2 7.0 1.2 NB. state 6 -- \u00
1.2 3.0 1.2 NB. state 7 -- \u000
)
evalbs=: [:; [:subst2 [:subst6 splitbs
NB. test suite for backslash evaluator
testbs=: (7 u: evalbs@[) assert@-: 4 u: ]
NB. ordinary text should remain unchanged
'abcd' testbs 97+i.4
NB. unicode escapes should work
'\u005c\U00a5\U20a9' testbs 92 165 8361
NB. backslash escapes should work
'\"\\\/\b\f\n\r\t' testbs 34 92 47 8 12 10 13 9
--
Raul
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