javaScript: Split one function into two

Question

I have the following working function (the lower part of it is not shown):

<script type="text/javascript">
function plan_click(clicked_id){
 let var_plan;
 let var_sgldbl;
 var_sgldbl = 'sgl';
 var_plan = clicked_id;
 document.getElementById(clicked_id).style.background = "green";
/* new code*/
 let var_tab01;
 switch (var_plan) {
 case '101':
 var_tab01 = 201;
 document.getElementById(var_tab01).style.background = "green";
 break;
}}
</script>

I want the function to be split into two functions at the /new code/ - in separate scripts as the new "tabeller" function might be placed in a js.-file. The "tabeller"-function should be called from the plan_click-function and receive the actual values from the variables: var_plan and var_sgldbl.

Which code should be inserted to make the split effective?

• Brad: For what you're doing, consider adding a class of like "select" or something and putting the styling in the CSS.

Answer 1

Just move the code out to another function. var_plan should be a parameter, while var_tab01 can be the return value.

function plan_click(clicked_id) {
 let var_plan;
 let var_sgldbl;
 var_sgldbl = 'sgl';
 var_plan = clicked_id;
 document.getElementById(clicked_id).style.background = "green";
 let var_tab01 = tabeler(var_plan);
 ...
}
function tabeler(var_plan)
 let var_tab01;
 switch (var_plan) {
 case '101':
 var_tab01 = 201;
 document.getElementById(var_tab01).style.background = "green";
 break;
 ...
 }
 return var_tab01;
}

• StackSlave: Looks okay, but it's a bad practice in JavaScript to reassign function arguments.
• Barmar: @StackSlave Since most functions don't use arguments (and the introduction of default values and ... in ES6 make it less necessary) I consider that not very persuasive.
• Barmar: Actually, I think I misunderstood the original code, and var_tab01 doesn't need to be a parameter.
• StackSlave: Yeah, OP probably doesn't know how to use function arguments. I just like to have that option. I also, like to use both kinds of functions. this!!!