Assign string variable to array using for loop

Question

I have a list of string variables and I want to assign all of these to an array, but the list is to much, is there any possible for me to using for loop to assign it.

var class_1 = "some description..";
var class_2 = "some description..";
var class_3 = "some description..";
var class_4 = "some description..";
var class_5 = "some description..";
.
. 
var class_100 = "some description..";

var classes = [];

for(var i = 0; i < 100; i++){

 //loop string variables to array    

}

I think it is not possible for me to assign 100 variables manually to the array. Anyone know any technique? Thank you.

[UPDATE] It requires in SystemVerilog syntax, since I not familiar in that language, so I present the idea in Javascript.

use a array .so instead of `class_1` you can use `class_[1]` — Madhawa Priyashantha, Nov 07 '16 at 02:19
@Fast Snail Those variables are pre-defined variables, so how can I just move to an array? — helloworld1234, Nov 07 '16 at 02:21
Probably it's better to parse file with those variables and populate them into array? Anyway, you can check also [this](http://stackoverflow.com/questions/5117127/use-dynamic-variable-names-in-javascript) — aring, Nov 07 '16 at 02:21
@helloworld1234 oops if it's pre defined list you cannot do that.sorry — Madhawa Priyashantha, Nov 07 '16 at 02:22
There is a team who share and define those variables, I get it from them.. — helloworld1234, Nov 07 '16 at 03:23
it looks like you need something like eval('some expression'), but i am not sure whether system-verilog supports this command or not — Alongkorn, Nov 07 '16 at 04:06

score 2 · Answer 1 · answered Nov 07 '16 at 04:53

There is no way in SystemVerilog to build an array of values from a list of independently named variables without manually assigning each variable to an element of an array.

classes[0] = class_0;
classes[1] = class_1;
classes[2] = class_2;
...

The fact that the identifiers used for variables names have a numerical sequence is of no consequence because you cannot access identifiers except by the exact name.
If you want to automate this, you will need to change the way the string variables are defined. As people have already posted, this should been modeled using an array to begin with, perhaps using an associative array:

string classes[string];
classes["class_1"] = "some description..";
classes["class_2"] = "some description..";
classes["class_3"] = "some description..";

foreach(classes[name])
       // do something with classes[name]

Another option is to use a SystemVerilog class object for each variable

class stringvar;
  string m_name;
  static stringvar list[$];
  function new(string name);
    m_name = name;
    list.push_back(this);
  endfunction 
endclass

stringvar class_0 = new("some description..");
stringvar class_1 = new("some description..");
stringvar class_2 = new("some description..");
...
foreach(stringvar::list[item])
   // do something with item.m_name

score 0 · Answer 2 · answered Nov 07 '16 at 02:25

0

Something like this:

var class_1 = "some description..";
var class_2 = "some description..";
var class_3 = "some description..";
var class_4 = "some description..";
var class_5 = "some description..";

var class_100 = "some description..";

var classes = [];
for(var i = 0; i < 100; i++){

 classes.push(window['class_'+i])

}

answered Nov 07 '16 at 02:25

aring

3,422
2
22
29

Thanks for answering, is it javascript syntax? How about in SystemVerilog? – helloworld1234 Nov 07 '16 at 02:28
@helloworld1234 Your original post syntax - **is** it SystemVerilog, or it is actually JavaScript? – aring Nov 07 '16 at 02:33

score 0 · Answer 3 · answered Nov 07 '16 at 02:27

You have 100 variables? You should sort that out first

I think there is some truth to that comment. But to answer your question: Assuming your variables follow the same naming convention that you example above shows, you can assign predefined variables with array values like so:

var a = []
for(var i = 0; i < num_vars; i++){
    var key = 'class_' + (i + 1)
    if (this[key])
        a.push(this[key])
}

score 0 · Answer 4 · answered Nov 07 '16 at 02:51

0

You perhaps can use eval. something like this:

for (var i = 0; i < 100; i++) {
    var toEval = "classes.push(class_" + i + ")";
    eval(toEval);
}

answered Nov 07 '16 at 02:51

Dina

937
9
12

is this in SystemVerilog language? – helloworld1234 Nov 07 '16 at 03:05

Assign string variable to array using for loop

4 Answers4