Would anyone be interested if I actually implemented support regex by
calling into the C library?
I'm envisioning something like this:
* "^([a-z]+):([0-9]+)$" regex∆scan "foo:123"*
┏→━━━━━━━━━━┓
┃"foo" "123"┃
┗∊━━━━━━━━━━┛
Regards,
Elias
On 22 June 2016 at 10:35, Xiao-Yong Jin <jinxiaoy...@gmail.com> wrote:
> At some point I really wanted to implement the simplest editor, namely ed
> (it would be much better than any APL system has offered), in APL, but I
> never finished the regex part. Perhaps it would be a nice exercise for
> someone who’s interested in learning APL to actually implement some of the
> most used Unix command line utilities.
>
> > On Jun 21, 2016, at 8:53 PM, Christian Robert <
> christian.rob...@polymtl.ca> wrote:
> >
> > Hi,
> >
> > A more general purpose search&replace (some bug fixed), take (2), was
> "snr".
> >
> >
> >
> > )sic
> > )erase replace
> > ∇z←s replace p;fr;to;P;i;⎕io
> > ⍝ -------------
> > →(2≤≡s)/ForEach
> > →(2≤⍴⍴s)/Matrix
> > →Vector
> > ⍝ -------------
> > ForEach: z←{⍵ replace p}¨s ◊ →0
> > Matrix: z←⊃ {⍵ replace p}¨ ⊂[2]s ◊ →0
> > ⍝ -------------
> > Vector: p←,¨p ◊ z←s←,s ⋄ ⎕io←1
> > Loop:→((⍴p)<2)/0
> > (fr to)←2↑p ◊ p←2↓p
> > P←¯1↓∧/[1](¯1+⍳⍴fr)⌽fr∘.=z,⎕ucs 1
> > i←0
> > Sanitize: i←i+1
> > →(i>(⍴P)-⍴fr)/Substitute
> > →(0=P[i])/Sanitize
> > ((⊂ i+¯1+⍳⍴fr)⌷P)←(⍴fr)↑1
> > →Sanitize
> > Substitute: P←⌽(P/⍳⍴P)
> > ⊣ {z←((¯1+⍵)↑z),to,(¯1+⍵+⍴fr)↓z}¨P
> > →Loop
> > ∇
> >
> > It should be vector, matrix and embedded objects "aware" (as long as it
> is all text)
> >
> > Syntax:
> >
> > source replace "this" "by_that" "this" "by_that" [...] (eg: pairs of
> "from" and "to")
> >
> > Examples:
> >
> > (⎕cr 'replace') replace 'replace' 'snr' 'ForEach' "Each"
> "Substitute" "Subst" "Sanitize" "Sane"
> > z←s snr p;fr;to;P;i;⎕io
> > ⍝ -------------
> > →(2≤≡s)/Each
> > →(2≤⍴⍴s)/Matrix
> > →Vector
> > ⍝ -------------
> > Each: z←{⍵ snr p}¨s ◊ →0
> > Matrix: z←⊃ {⍵ snr p}¨ ⊂[2]s ◊ →0
> > ⍝ -------------
> > Vector: p←,¨p ◊ z←s←,s ⋄ ⎕io←1
> > Loop:→((⍴p)<2)/0
> > (fr to)←2↑p ◊ p←2↓p
> > P←¯1↓∧/[1](¯1+⍳⍴fr)⌽fr∘.=z,⎕ucs 1
> > i←0
> > Sane: i←i+1
> > →(i>(⍴P)-⍴fr)/Subst
> > →(0=P[i])/Sane
> > ((⊂ i+¯1+⍳⍴fr)⌷P)←(⍴fr)↑1
> > →Sane
> > Subst: P←⌽(P/⍳⍴P)
> > ⊣ {z←((¯1+⍵)↑z),to,(¯1+⍵+⍴fr)↓z}¨P
> > →Loop
> >
> >
> > You can even try "⎕fx" the result if it looks like Ok. (ps: always check
> the result before committing)
> >
> > Substitutions are done in pair sequence for each /vector/matrix/embedded
> obj.
> >
> > So replace order is *very* important.
> >
> > It must still have some bugs, report them to me, with examples if so.
> Will do my best but no promises.
> >
> > Purpose: well, not sure, it was an exercise. I used it on itself to
> finally rename the function and change some variables/labels names.
> >
> >
> > Features: would be fun to pass parameters to each of the /from/to/ like
> maximum number of substitutions to do per line ...
> > whole words only (taking apl characters as blanks) ... so
> variable "s" won't match last character of variable "pairs"
> > ... no limits
> >
> >
> > Xtian.
> >
> >
> > On 2016-06-21 12:27, Juergen Sauermann wrote:
> >> Hi Xtian,
> >>
> >> how about this:
> >>
> >> *
> **s←"444This4is4a4444test44with44444lot4of4blanks4444at4beginning4and444end444444"**
> >> from←"444"**
> >> ** to←"5"**
> >> **
> >> ** ↑⍎')HOST echo "',s,'" | sed s/',from,'/',to,'/g'**
> >> **5This4is4a54test44with544lot4of4blanks54at4beginning4and5end55**
> >> ** **
> >> *I have replaced the *^* in your example because it (and some other
> characters) have a special meaning in
> >> regular expressions. But the special characters can be easily quoted in
> APL if needed, for example:
> >>
> >> *
> s←"^^^This^is^a^^^^test^^with^^^^^lot^of^blanks^^^^at^beginning^and^^^end^^^^^^"
> **
> >> ** ((s='^')/s)←⊂'\^'**
> >> ** ⊃,/s**
> >>
> **\^\^\^This\^is\^a\^\^\^\^test\^\^with\^\^\^\^\^lot\^of\^blanks\^\^\^\^at\^beginning\^and\^\^\^end\^\^\^\^\^\^**
> >> *
> >> /// Jürgen
> >>
> >>
> >> On 06/21/2016 05:12 AM, Christian Robert wrote:
> >>> Hi, it's not a bug but a request for help,
> >>>
> >>>
> >>> suppose
> s="^^^This^is^a^^^^test^^with^^^^^lot^of^blanks^^^^at^beginning^and^^^end^^^^^^"
> >>> suppose from="^^^"
> >>> suppose to="^"
> >>>
> >>> I need a function who can replace ("^^^" to "^"), or ("^" to
> "^^^^^^^^") or ("" to "blabla" with limits of source size) ie: without
> being lost in infinite loop.
> >>>
> >>>
> >>>
> >>> "s" is a character vector, "from" is a character vector, and "to" is a
> character vector,
> >>> both "s", "from" and "to" can be "".
> >>>
> >>>
> >>>
> >>> I'm pretty sure this idiom already exist.
> >>>
> >>> if you can help me, please do.
> >>>
> >>> Xtian.
> >>>
> >>>
> >>>
> >>>
> >>>
> >>>
> >>
>
>
>
