Get type of generic parameter -

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i wrote small function better handling types.

function evaluate(variable: any, type: string): {     switch (type)     {         case 'string': return string(variable);         case 'number': return isnumber(variable) ? number(variable) : -1;         case 'boolean': {             if (typeof variable === 'boolean')                 return variable;              if (typeof variable === 'string')                 return (<string>variable).tolowercase() === 'true';              if (typeof variable === 'number')                 return variable !== 0;              return false;         }         default: return null;     } }  function isnumber(n: any): boolean {     return !isnan(parsefloat(n)) && isfinite(n); }

i try same generics, don't know how type generic parameter. it´s possible?

typeof javascript operator. can used @ run time types javascript knows about. generics typescript concept helps check correctness of code doesn't exist in compiled output. short answer no, it's not possible.

but this:

class holder<t> {     value: t;     constructor(value: t) {         this.value = value;     }     typeof(): string {         return typeof this.value;            } }

try out.

this works because i'm operating on value inside holder, not on holder itself.


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