[Bug-apl] Readline is gone

[Juergen Sauermann]

Hi,

after more than 6 years a good old friend, libreadline, has ceased to exist in GNU APL.

Its main capabilities (as far as GNU APL is concerned) have been replaced by similar but
more APL aware functions that I would like to mentioned here:

1. Line history (aka. cursor up/down keys).

There are now different histories for different input contexts. For example, cursor-up in ⍞-input
recalls the previous line entered in ⍞-input and not just the last line entered (possibly in a different context).
Likewise for ⎕. The history file contains the history of lines entered in immediate execution; the ⍞ and ⎕
histories are rather short and lost when the interpreter exits.

Functions entered in the ∇-editor are now inserted in display [⎕] order and not in the order of the user lines entered.
This makes a replay of the history for defined functions possible.

Inside the ∇-editor, cursor up-down recalls the other function lines (a feature missing so far in the ∇-editor).

2. Tab completion (aka tab key) is more APL aware:

2a. . (dot = current directory) and / start the usual filename completion
2b. ] and ) start APL command name completion and, to some extent, command argument completion
2c. ⎕ starts system variable and function names completion,
2d. A-Z, a-z, ∆,⍙ etc start user-defined name completion.

SVN 465, I hope you like it.

/// Jürgen