Question

I am trying to get text in a selection to be passed to the function
find_max_eq_filter originally. The function I am trying to modify had an
“s” parameter which I assume is the selection text. I want to change the
function to allow a parameter that is passed by the user. Could someone
clue me in how to do this?

    _command void align_equals() name_info(','VSARG2_MARK|VSARG2_REQUIRES_EDITORCTL)
    {

       if ( _select_type() != "LINE" && _select_type() != "BLOCK" ) {
          message("A LINE or BLOCK selection is required for this function");
          return;
       }

       gMaxEqCol = 0;

       _str character = prompt(prmt1, 'What do you wish to align?'); /* I want to ask the user for an input string */
       filter_selection(find_max_eq_filter(s, character));  /* Here I want to pass the selection with the string taken from the user. */

       if (gMaxEqCol == 0) {
          // no equal signs
          return;
       }

       filter_selection(align_eq_filter);
       _free_selection("");
    }


    static _str find_max_eq_filter(s, _str toalign)
    {
       _str inputStr = expand_tabs(s)
       int equalsPos = pos(toalign, inputStr, 1, "");
       if ( equalsPos > gMaxEqCol  ) {
          gMaxEqCol = equalsPos;
       }

       return s;
    }

filter_selection(find_max_eq_filter);

Any help appreciated,

Ted

PS. you want to reproduce what I am doing so I’ll have to paste the whole thing:

     #include "slick.sh"

     static int gMaxEqCol;
     static _str gUsrStr;

     static _str find_max_char_filter(s)
     {
        _str inputStr = expand_tabs(s);
        int equalsPos = pos(gUsrStr, inputStr, 1, "");
        if ( equalsPos > gMaxEqCol  ) {
           gMaxEqCol = equalsPos;
        }

        return s;
     }

     static _str align_char_filter(s)
     {
        if (gMaxEqCol <= 0 || length(s) == 0) {
           return s;
        }

        _str expandedStr = expand_tabs(s);

        int equalsPos  = pos(gUsrStr, expandedStr, 1, "");
        if (equalsPos == 0) {
           return s;
        }

        _str prefix    = substr(expandedStr, 1, equalsPos - 1);
        _str postfix   = substr(expandedStr,equalsPos);

        while (equalsPos < gMaxEqCol ) {
           prefix = prefix :+ ' ';
           ++equalsPos;
        }

        return prefix :+ postfix;
     }

     _command void align_chars() name_info(','VSARG2_MARK|VSARG2_REQUIRES_EDITORCTL)
     {

        if ( _select_type() != "LINE" && _select_type() != "BLOCK" ) {
           message("A LINE or BLOCK selection is required for this function");
           return;
        }

        gMaxEqCol = 0;
        _str prmpt1 = "";
        gUsrStr   = prompt(prmpt1, "Please enter a string: ");
        filter_selection(find_max_char_filter);

        if (gMaxEqCol == 0) {
           // no equal signs
           return;
        }
        filter_selection(align_char_filter);
        _free_selection("");
     }

So this is my problem, I want to change gUsrStr to be a parameter of the helper functions instead of having a global variable for it. However, when I try to do that it breaks. Also, I do not quite understand the first argument of the prompt function. What is it suppposed to be? Is it a default value in case the user does not enter anything?

Answer 1

You are not posting the relevant part,
I think you should post the header of the calling function …

But I’ll try my hand at a partial answer, then update if you update the question …

Does it have any of these tags?
VSARG2_REQUIRES_AB_SELECTION, or VSARG2_REQUIRES_SELECTION (or really anything with REQUIRE and SELECTION – if so try to remove them

Are there any select_active() checks? follow those or disable them

Also are you trying to invoke it interactively or just from another slick-c code?

Many years ago I figured some of this out when I wrote narrow.e, allowing me to emulate emacs’ narrow-to-region. I used it to base my answer (narrow.e is posted here for the full example).