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@greggirwin
Last active November 9, 2018 08:04
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Red ENTAB/DETAB mezzanines
Red []
; Steeve gets credit for this one
detab: function [
"Converts leading tabs in a string to spaces. (tab size 4)"
string [any-string!] "(modified)"
/size
sz [integer!] "Number of spaces per tab"
/all "Change all, not just leading"
][
sz: max 1 any [sz 4] ; size must be at least 1
buf: append/dup clear " " space sz
parse string [
BOL: some [
; If we see a tab, mark its position, then change it to the...ready?
; offset into our buffer of spaces, based on the the difference
; between our current position and the beginning of the line, modulo
; the tab size.
pos: change tab (skip buf (offset? BOL pos) % sz)
| lf BOL: ; Set our beginning-of-line marker
| if (all) to [tab | lf] ; Skip over non-tab chars
| space ; Spaces just move us forward in the line
| thru lf BOL: ; Skip to end of line and set our marker
]
]
string
]
detab-tests: [
"" ""
"^-" " "
" ^-" " "
" ^-" " "
" ^-" " "
" ^-" " "
" ^-" " "
" ^- ^-" " "
" ^- ^-" " "
" ^- ^-^-" " "
" ^- ^-^-^-" " "
"^-abc^-" " abc^-"
"^-abc^-^/" " abc^-^/"
"^-abc^-^/^-def^-" " abc^-^/ def^-"
" ^- ^-^-" " "
"^-abc ^-" " abc ^-" ; 10
" ^- ^-^-^-" " " ; 16
" ^- ^-^-" " " ; 16
]
foreach [inp out] detab-tests [
if out <> res: detab inp [
print ['FAIL! 'expected mold out "but got" mold res]
]
]
detab-tests: [
"^-abc^-" " abc " ; 8
"^-abc ^-" " abc " ; 12
"^-abc^-^/^-def^-" " abc ^/ def " ; 17
]
foreach [inp out] detab-tests [
if out <> res: detab/all inp [
print ['FAIL! 'expected mold out "but got" mold res]
]
]
detab-tests: [
"^-" 2 " "
" ^-" 2 " "
" ^-" 2 " "
" ^- ^-^-^-" 2 " "
" ^- ^- ^-^-" 2 " "
]
foreach [inp sz out] detab-tests [
if out <> res: detab/size/all inp sz [
print ['FAIL! 'expected mold out "but got" mold res]
]
]
;-------------------------------------------------------------------------------
entab: function [
"Converts leading spaces in a string to tabs. (tab size 4)"
string [any-string!] "(modified)"
/size
sz [integer!] "Number of spaces per tab (must be at least 1)"
/all "Change all, not just leading"
][
sz: max 1 any [sz 4] ; size must be at least 1
sz-1: max 1 sz - 1 ; can't have 0 as a m..n size for parse
parse string [
some [
any [change sz space tab | change [1 sz-1 space tab] tab]
if (not all) [thru [newline | end]]
| skip
]
]
string
]
entab-tests: [
"" ""
" " "^-"
" ^-" "^-"
" ^-" "^-"
" ^-" "^-"
" ^-" "^-^-"
"a b c d e f g" "a b c d e f g"
" a b c d e f g" "^-a b c d e f g"
"a b c d e f g " "a b c d e f g "
" a b c d e f g " " a b c d e f g "
" a b c d e f g " "^-^-a b c d e f g "
"a b c^/ d e f g" "a b c^/^-d e f g"
"a b c^/ d e f g" "a b c^/^-d e f g"
" a b c^/ d e f g^/ " "^-a b c^/^-d e f g^/^-"
]
foreach [inp out] entab-tests [
if out <> res: entab inp [
print ['FAIL! 'expected mold out "but got" mold res]
]
]
entab-tests: [
{ a ^/ b ^/ c d e f g^/ } 2 {^-^-^-^-a ^/ b ^/ c d e f g^/^-^-}
{ a ^/ b ^/ c d e f g^/ } 2 {^-^-a ^/ b ^/ c d e f g^/^-}
]
foreach [inp sz out] entab-tests [
if out <> res: entab/size inp sz [
print ['FAIL! 'expected mold out "but got" mold res]
]
]
entab-tests: [
"a b c d e f g" 4 "a b c^-d e f g"
" a b c d e f g" 4 "^-a b c^-^-d e f g"
"a b c d e f g " 4 "a b c^-^-d e f g^-"
" a b c d e f g " 4 " a b c^- d e f g "
" a b c d e f g " 4 "^-^-a b c^-^-d e f g^-^-"
{ a} 1 {^-a}
{ a ^/ b ^/ c d e f g^/ } 2 {^-^-^-^-a^-^-^/ b^-^-^/ c^-^-^-^-d e f g^/^-^-}
{ a ^/ b ^/ c d e f g^/ } 2 {^-^-a^-^/ b^-^/ c^-^-d e f g^/^-}
]
foreach [inp sz out] entab-tests [
if out <> res: entab/size/all inp sz [
print ['FAIL! 'expected mold out "but got" mold res]
]
]
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