src/eMacros/Runtime/Symbol/SymbolExists.php
public function apply(Scope $scope, GenericList $arguments) {
		if (count($arguments) == 0) throw new \BadFunctionCallException("SymbolExists: No parameters found.");
		$ref = $arguments[0]->evaluate($scope);
		if (!is_string($ref) || empty($ref))
			throw new \InvalidArgumentException("SymbolExists: Symbol must be specified as a non-empty string.");
		return array_key_exists($ref, $scope->symbols);
	}
public function apply(Scope $scope, GenericList $arguments) {
		if (count($arguments) == 0) throw new \BadFunctionCallException("SymbolExists: No parameters found.");
		$ref = $arguments[0]->evaluate($scope);
		if (!is_string($ref) || empty($ref))
			throw new \InvalidArgumentException("SymbolExists: Symbol must be specified as a non-empty string.");
		return array_key_exists($ref, $scope->symbols);
	}
Checks if the given symbol exists on current environment
Usage: (sym-exists "true") (sym-exists "_value")
Returns: boolean
(non-PHPdoc)
@see \eMacros\Applicable::apply()