我开始皈依
http://www.rebol.org/view-script.r?script=csv-tools.r
从Rebol到Red;我被困在二进制的“字符串”上,在Rebol上找不到关于它们的文档。
to-iso-date: func [
"Convert a date to ISO format (Excel-compatible subset)"
date [date!] /utc "Convert zoned time to UTC time"
] [
if utc [date: date + date/zone date/zone: none] ; Excel doesn't support the Z suffix
either date/time [ajoin [
next form 10000 + date/year "-"
next form 100 + date/month "-"
next form 100 + date/day " " ; ... or T
next form 100 + date/time/hour ":"
next form 100 + date/time/minute ":"
next form 100 + date/time/second ; ... or offsets
]] [ajoin [
next form 10000 + date/year "-"
next form 100 + date/month "-"
next form 100 + date/day
]]
]
to-csv: func [
"Convert a block of values to a CSV-formatted line in a string."
[catch]
data [block!] "Block of values"
delimiter [char! string! binary!] {Default ","}
; Empty delimiter, " or CR or LF may lead to corrupt data
][
output: make block! 2 * length? data
delimiter: either with [to-string delimiter] [","]
unless empty? data [insert tail output format-field first data data: next data]
foreach x data [insert insert tail output delimiter format-field get/any 'x]
to-string output
format-field: func [x [any-type!]] [case [
any [not value? 'x error? get/any 'x] [throw-error 'script 'expect-set [
[any-string! any-word! any-path! binary! scalar! date!] type? get/any 'x
]]
none? :x [""]
any-string? :x [ajoin [{"} replace/all copy x {"} {""} {"}]]
:x == #"^(22)" [{""""}] ; Weirdly, = and =? return true when x is 34
char? :x [ajoin [{"} x {"}]]
money? :x [find/tail form x "$"]
scalar? :x [form x]
date? :x [to-iso-date x]
any [any-word? :x binary? :x any-path? :x] [
ajoin [{"} replace/all to-string :x {"} {""} {"}]
]
'else [throw-error 'script 'expect-set reduce [
[any-string! any-word! any-path! binary! scalar! date!] type? :x
]]
]]
]
load-csv: func [
"Load and parse CSV-style delimited data. Returns a block of blocks."
[catch]
source [file! url! string! binary! block!] "File or url will be read"
/binary "Don't convert the data to string (if it isn't already)"
delimiter [char! string! binary!] {Default #","}
/into "Insert into a given block, rather than make a new one"
output [block!] "Block returned at position after the insert"
/part "Get only part of the data, and set to the position afterwards"
count [integer!] "Number of lines to return"
after [any-word! none!] "Set to data at position after decoded part"
] [
if block? source [ ; Many sources, load them all into the same output block
unless into [output: make block! length? source]
unless with [delimiter: ","]
x: [file! url! string! binary!]
foreach y source [
unless find x type?/word y [
cause-error 'script 'expect-set reduce [x type? :y]
]
either binary [
output: load-csv/binary/with/into y delimiter output
] [
output: load-csv/with/into y delimiter output
]
]
return either into [output] [head output]
]
; Read the source if necessary
if any [file? source url? source] [throw-on-error [
source: either binary [read/binary source] [read source]
]]
unless binary [source: as-string source] ; No line conversion
; Use either a string or binary value emitter
emit: either binary? source [:as-binary] [:as-string]
; Prep output and local vars
unless into [output: make block! 1]
line: [] val: make string! 0
; Parse rules
valchars: remove/part charset [#"^(00)" - #"^(FF)"] crlf
case [
any [char? delimiter: any [delimiter ","] last? delimiter] [ ; One char
valchars: compose [any (remove/part valchars delimiter)]
]
empty? delimiter [throw-error 'script 'invalid-arg delimiter]
'else [ ; Multi-character delimiter needs special handling
remove/part valchars copy/part as-string delimiter 1
valchars: compose/deep [any [
some (valchars) | y: delimiter :y break | (first as-string delimiter)
]]
]
]
value: [
; Value in quotes, with Excel-compatible handling of bad syntax
{"} (clear val) x: [to {"} | to end] y: (insert/part tail val x y)
any [{"} x: {"} [to {"} | to end] y: (insert/part tail val x y)]
[{"} x: valchars y: (insert/part tail val x y) | end]
(insert tail line emit copy val) |
; Raw value
x: valchars y: (insert tail line emit copy/part x y)
]
part: pick [ ; Rule must fail and go to the alternate in order to continue
[end skip] ; Will always fail, so the break won't be reached
[(cont: if positive? count [count: count - 1 [end skip]]) cont]
; While count is positive, cont is set to [end skip], which will fail
; and go the alternate. Otherwise, cont is set to none, which will
; succeed, and then the subsequent break will stop the parsing.
; Parsing control flow can get a little convoluted at times in R2.
] not part
; as-string because R2 doesn't parse binary that well
parse/all as-string source [z: any [
end break | part break |
(line: make block! length? line)
value any [delimiter value] [crlf | cr | lf | end]
(output: insert/only output line)
] z:]
if after [set after either binary? source [as-binary z] [z]]
also either into [output] [head output]
(source: output: line: val: x: y: none) ; Free the locals
]
