$.stack is not a string

Community Expert ,
Feb 14, 2017 Feb 14, 2017

Copy link to clipboard

Copied

ESTK and FDK documentation and even typeof claims that $.stack is a string. If it is printed with $.writeline it behaves as such and creates multiple lines.
I want to build a function which can be called in any routine and will then indicate the calling level by indentation and the name of the function.
For that puprose I wanted to split the 'string' into an array, the length of which indicating the nesting level of the function in question.
But it turns out that $.stack can not be handled as a string:

function ZTrace () {
// $.stack is not a string - what is it?
var level, aStack = [], s1Stack, s2Stack;
  s1Stack = toHex($.stack);
  $.writeln (s1Stack);                    // see what it looks like    
  s2Stack = $.stack.toString();           // sStack behaves as stack
  aStack = s2Stack.split (hex2a("829a")); // does not split
  level = aStack.length;                  // always 1
  $.writeln (aStack[0]);                  // always full stack
  $.writeln (aStack[1]);                  // undefined
} // --- end ZTrace

function toHex(str) {
    var hex = '';
    for(var i=0;i<str.length;i++) {
        hex += ''+str.charCodeAt(i).toString(16);
    }
    return hex;
}

function hex2a(hexx) {
// http://stackoverflow.com/questions/3745666/how-to-convert-from-hex-to-ascii-in-javascript
// hex2a('32343630'); // returns '2460'
    var hex = hexx.toString();//force conversion
    var str = '';
    for (var i = 0; i < hex.length; i += 2)
        str += String.fromCharCode(parseInt(hex.substr(i, 2), 16));
    return str;
}

For example, in a nested function calling ZTrace () will create a stack like this

[ZTrace-test.jsx]
Level_0()
Level_1()
Level_2()
Level_3()
ZTrace()

But the line 05 creates (here both in hex and interpreted):

5b5a54726163652e6a73785da4c6576656c5f302829a4c6576656c5f312829a4c6576656c5f322829a4c6576656c5f332829a5a54726163652829a
[ Z T r a c e . j s x ] ¤ Æ W f u Å ó ??????L e v e l _ 1 ( ) ¤ Æ W f V Å ó ??????L e v e l _ 3 ( ) ¥ ¥ G ????6 R ????


Now, of what type is $.stack?

TOPICS
Scripting

Views

301

Likes

Translate

Translate

Report

Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines

correct answers 1 Correct answer

Engaged , Feb 14, 2017 Feb 14, 2017

Hi Klaus,

$.stack is a string

$.writeln(typeof($.stack)) prints "string"

This

aStack = s2Stack.split ("\n");

does exactly, what I expected. I get an Array of lines, and the following lines of code deliver the expected results.

  level = aStack.length;             

  $.writeln (aStack[0]);                 

  $.writeln (aStack[1]);               

Last item in Array is an empty string, so level is aStack.length - 1 and perhaps -1 for the Name of the script file.

Not sure why you are doing this hex stuff.

...

Likes

Translate

Translate
Engaged ,
Feb 14, 2017 Feb 14, 2017

Copy link to clipboard

Copied

Hi Klaus,

$.stack is a string

$.writeln(typeof($.stack)) prints "string"

This

aStack = s2Stack.split ("\n");

does exactly, what I expected. I get an Array of lines, and the following lines of code deliver the expected results.

  level = aStack.length;             

  $.writeln (aStack[0]);                 

  $.writeln (aStack[1]);               

Last item in Array is an empty string, so level is aStack.length - 1 and perhaps -1 for the Name of the script file.

Not sure why you are doing this hex stuff. I think this is not necessary.

In your case hex2a allways delivers an empty string, and this is why aStack.length is always 1.

hope this helps

Markus

Likes

Translate

Translate

Report

Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
Engaged ,
Feb 14, 2017 Feb 14, 2017

Copy link to clipboard

Copied

BTW:

str += String.fromCharCode(hex.substr(i, 2)); 

always delivers two not visible characters for "829a" assuming these two characters are not defined as charater within Unicode (here I was wrong as I said string is empty)

hex2a("647E")

works and delivers "d~" as there are characters defined

and

hex2a("0a")

delivers the linefeed and Splitting works

var del = hex2a("0a");

Stack = s2Stack.split (del);

but this is equal to

Stack = s2Stack.split ("\n");

Likes

Translate

Translate

Report

Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
Community Expert ,
Feb 14, 2017 Feb 14, 2017

Copy link to clipboard

Copied

Thanks Markus,

The hex business 'was necessary' because initially I did not split with "\n", but with "\\n" - which obviously is wrong... Analysing what is really in the string lead me to this erraneous deviation.

The ZTrace function now is this:

function ZTrace () { //==== Indicate calling sequence =============================================
// Returns  -
// Called by if (settings.IsDebug) {ZTrace ();}
var indent, name, level, aStack = [], sStack, 
    dots = ".......................................................................................";
  sStack = $.stack.toString();
  aStack = sStack.split ("\n");
  level = aStack.length - 3;
  if (level > 0) {name = aStack[level]};
  indent = dots.substring(0, level*2);
//Console (indent + name);
  $.writeln (indent + name);
} // --- end ZTrace

Likes

Translate

Translate

Report

Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
Engaged ,
Feb 14, 2017 Feb 14, 2017

Copy link to clipboard

Copied

LATEST

Hi Klaus,

glad you got this job done.

Here is a list of relevant escape sequences:

CodeOutputsHex Code
\'single quote0x27
\"double Quote0x22
\\backslash0x5C
\rCarriage Return0x0d
\nLine feed0x0a
\tHorizontal Tabulator0x09

For more Information visit: https://www.w3schools.com/js/js_strings.asp

double backslash means a realworld backslash, so you split statement searched for the real world string "\n" and not for the character "Linfeed (0x0a)".

Hope this helps anybody

Markus

Likes

Translate

Translate

Report

Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines