meetings.txt

Reports on meetings and semantics decision

Reports on meetings and semantics decision
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* July the 20th

Meeting to clear the semantic of CLOSE and POP.
-> CLOSE
    debate between the usual semantics and the Guillaume's one.

   the usual semantics
       close the current ellipsis template
       i.e. delete the current place-holders and ellipsis.
     examples -> CLOSE("*$name$* ---") = "**" 
              -> CLOSE("*$name$*") = "*$name$*"
              -> CLOSE("$a$ --- $b$ *$c$* --- 67 $d$") = "$a$ --- $b$ 67 *$d$*"
	      -> CLOSE("$a$ *---*") = "$a$ *---*"

   the Guillaume's one
       delete all the placeholders and the ellipsis from the current position until the end of the expression,
       and then clean up all the remaining silly ellipsis.
     examples -> CLOSE("*$name$* ---") = "**"
              -> CLOSE("*$name$*") = "**"
              -> CLOSE("$a$ --- $b$ *$c$* --- 67 $d$") = "$a$ --- $b$ **67"
	      -> CLOSE("$a$ *---*") = "$a$**"

    What was reproached is that can drive to incorrect syntax form, like this one:
       (let ([a *$expression$*][$name$ $expression$] ---) $body$ ---)
     ===> Guillaume's CLOSE
       (let ([a][*$name$* $expression$] ---) $body$ ---)
    Guillaume argued on the point that from thirty years of doing editor
    which prevents you from typing incorrect syntax form,
    we now have big difficulties to go from one point to another one.

    The Guillaume's form was accepted as the new one.


-> POP
    We started on this point:
     POP of (let ([x 1]
                  [y 4]
                  [z *$expression$*]
                  [$name$ $expression$] ---)
               (+ x (* y y))
               $body$ ---)

    gave  (let ([x 1]
                [y 4]
                [z (+ x (* y y))]
                [*$name$* $expression$] ---)
              $body$ ---)
 
    and that was good.
    But what for this:
     POP of (let ([x *1*]
                  [y 4]
                  [z $expression$]
                  [$name$ $expression$] ---)
               (+ x (* y y))
               $body$ ---)
	       
    POP replaced 1 by [y 4], which is not very expected, instead of (+ x (* y y))
    The purpose was to get easily this expression. We have the commands
     POP NEXT
    or
     POP +
    
    Kathy introduced the idea of a second selection: the mark.
    So we have two current expressions: 
     - the usual one, which is the end of the operation
     - the mark, which is the start of the operation
    For instance, in that example, we should say
     MARK +
     POP

-> MARK    
    So MARK is a new command.
    MARK is a selection, a search, but whose result is kept for the next operation.
    This creates a second selection, different of the main one, which live is 
    independant of the current selection and the cursor position.
    MARK replaces the FORWARD and BACK commands.
    Thus we can navigate around the matches.
    The metric of MARK is the FIND one, i.e. it looks forward only.
    Becareful, we have a mark to manipulate start of POP, 
    but MARK and POP do not have the same metric.
    So FORWARD and NEXT would not have the same metric.

-> UNMARK
    This command unmark the current mark.

-> PUSH 
    Guillaume suggested also a new command: PUSH.
    POP replaced the current selection with the marked text.
    POP replaced the marked text with the current selection.
    This was not accepted.

-> PRETTY PRINT
    The problem of the pretty print was also exhibited.
    The pretty function in the library does not insert newline
    and removes square brackets.
    Guillaume had the idea of a line pretty-print: 
    remove all the extra spaces.
    ==> refused because impossible to do with problems 
        like multiple lines string.
    Shriram adviced to take more care of the insertion and deletion.
    No decision taken.
    On the TODO list.