[Bug-apl] My latest "edit" function

[Christian Robert]

My latest "edit" function. VERY useful to edit a function with "vi" editor 
while *inside* the interpreter.

The important part of this function I got from some post long ago making "vi" or 
"vim" working inside the interpreter,
mainly:

SaveTTY←⎕IO⊃⍎')HOST stty -g'
⊣⍎')HOST >/dev/tty stty sane'⊣⍎')HOST >/dev/tty ','vi',' ',fs_name
⊣⍎')HOST >/dev/tty stty ',SaveTTY

Usage:

      edit 'some_function_name'

and with

      ]usercmd ]edit {edit(⎕IO+1)⊃⍵←⍺}    ⍝  assuming you are at the latest SVN

you can call it with

      ]edit some_function_name      ⍝ without the quotes around the function 
name.


here it is:

      )sic
      )erase  edit
      ∇R←skipwrite edit funct;fd;lines;fs_name;z;r;SaveTTY
R←''                                                     ⍝ Always return ''
fs_name←'tmp/', 18 ⎕cr funct                             ⍝ The file name in the 
filesystem
⊣ (⎕FIO[20] 'tmp')                                       ⍝ mkdir tmp
⍝ ---------------------------------------------------------------------------
⍝ Check if it is  a request to reedit the previous written file in filesystem
⍝ very usefull in case of a syntax error while ⎕fx 'ing the function ...
⍝ ---------------------------------------------------------------------------
→(2=⎕nc 'skipwrite')/SkipWrite                           ⍝ If a left arg then 
skip write to the file
lines←{(⎕ucs 10),⍨(∼⌽∧\⌽⍵=' ')/⍵} ¨ ⊂[⎕io+1] ⎕cr funct   ⍝ The lines of the 
function
⍝ --------------------------------------------------
⍝ write the contents of this "funct" into the file
⍝ --------------------------------------------------
→(0>fd← "w" ⎕FIO[3] fs_name)/Error                       ⍝ Open for writing
⊣ {⍵ ⎕FIO[23] fd} ¨ lines                                ⍝ write all lines
⊣ (⎕FIO[4] fd)                                           ⍝ Close the file
⍝ --------------------------------------------------
⍝ Now do the actual edition ...
⍝ --------------------------------------------------
SkipWrite:
SaveTTY←⎕IO⊃⍎')HOST stty -g'
⊣⍎')HOST >/dev/tty stty sane'⊣⍎')HOST >/dev/tty ','vi',' ',fs_name
⊣⍎')HOST >/dev/tty stty ',SaveTTY
⍝ ----------------
⍝ and try ⎕fx it
⍝ ----------------
→(0≠"r" ⎕fio[31] fs_name)/Error                          ⍝ Can not read file ? 
→ Error
z←⎕fio[26] fs_name                                       ⍝ First pass, read the 
whole file
lines←⍳+/((↑"\n")=z)                                     ⍝ Compute the iota for 
each line
z←(⍴lines)⍴⍬                                             ⍝ Preallocate "z" to 
the right size
fd←⎕fio[3] fs_name                                       ⍝ Open the file
⊣ {⊣z[⍵]←⊂19 ⎕cr ⎕ucs ¯1↓(⎕fio[8] fd)} ⍤0 lines          ⍝ Put each line in the 
preallocated "z"
⊣ (⎕fio[4] fd) ⋄ →Fix                                    ⍝ Close the file and 
⎕FX it
Error: ⎕ES ∊'Error on file "',fs_name,'": ',⎕fio[2] | ⎕fio[1] ''
Fix: r←⎕fx z
⍝ 
----------------------------------------------------------------------------------------
⍝ Well, if "r" is an integer then it is a syntax error, if it is a string then 
it succeed.
⍝ 
----------------------------------------------------------------------------------------
⍝
→(0=↑0⍴r)/Syntax                                         ⍝ number → then a 
systax error
Ok: ⎕←∊ "Function '" (r) ("' saved.") ⋄ →0               ⍝ Probably a succesfull "save" 
or "save as"
⍝ ----------------------------------
⍝ We get here on errors while saving
⍝ ----------------------------------
Syntax:
9 ⎕cr ∊(∊'Line' (r-1) 'is in error: ') (∊z[r])
"Beware that you can not edit a running function or a suspended function on the stack, try 
)sic before launching \"edit\"."
∊ "Syntax error at line:" (r-1) ("( Use: 1 edit '" funct "' ) to have a chance to 
fix it without having to reenter all your latest changes.")
''
∇