6 examples of 'check type of variable in javascript' in JavaScript

442
function isTypeVariableInScope(id, state) {
443
  return state.g.typeVariableScopeDepth[id.name] > 0;
444
}

339
checkVarStatement(
340
  statement: VarStatement,
341
  define: (name: string, type: any) => void,
342
) {
343
  const initializerType = this.evaluate(statement.initializer);
344
345
  if (statement.type) {
346
    const variableType = this.scope.lookup(statement.type);
347
    checkTypeAssignable(initializerType, variableType, statement.name);
348
    define(statement.name.lexeme, variableType);
349
  } else if (initializerType) {
350
    define(statement.name.lexeme, initializerType);
351
  } else {
352
    error(statement.name, "cannot declare without type");
353
  }
354
}

3
function getVariableType(variable) {
4
    if (typeof variable == 'object') {
5
        if (variable instanceof Function) {
6
            return 'function';
7
        } else if (variable instanceof Array) {
8
            return 'array';
9
        } else if (variable instanceof HTMLElement) {
10
            return 'html'
11
        }
12
13
        return 'object';
14
    }
15
16
    return typeof variable;
17
}

189
function isVarType(t) {
190
    return (t.type === 'var');
191
}

47
function checkVariable(decl: TSESTree.VariableDeclaration, context: Rule.RuleContext) {
48
  if (decl.declare) {
49
    return;
50
  }
51
  decl.declarations.forEach(declaration =>
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    resolveIdentifiers(declaration.id).forEach(id =>
53
      raiseOnInvalidIdentifier(id, "local variable", context),
54
    ),
55
  );
56
}

28
function checkType(type) {
29
  const isArray = Array.isArray(input)
30
  return type == 'array' && isArray || (type === typeof input && !isArray)
31
}