src/core/class-papi-core-meta-store.php
public function format_value( $slug, $value ) {
		$slug     = strtolower( unpapify( $slug ) );
		$property = $this->property( $slug );

		// If no property type is found, just return null.
		if ( ! papi_is_property( $property ) ) {
			return;
		}

		// Format the value from the property class.
		$value = $property->format_value( $value, $slug, $this->id );

		// Only fired when not in admin.
		if ( ! papi_is_admin() ) {
			$value = papi_filter_format_value(
				$property->type,
				$value,
				$slug,
				$this->id,
				papi_get_meta_type()
			);
		}

		// Modify value before it's return to the theme via a defined format callback on the property.
		if ( ! papi_is_admin() && is_callable( $property->format_cb ) ) {
			$value = call_user_func( $property->format_cb, $value );
		}

		// Remove empty values from arrays.
		if ( is_array( $value ) ) {
			foreach ( $value as $index => $val ) {
				if ( papi_is_empty( $val ) ) {
					unset( $value[$index] );
				}
			}
		}

		return $value;
	}
public function format_value( $slug, $value ) {
		$slug     = strtolower( unpapify( $slug ) );
		$property = $this->property( $slug );

		// If no property type is found, just return null.
		if ( ! papi_is_property( $property ) ) {
			return;
		}

		// Format the value from the property class.
		$value = $property->format_value( $value, $slug, $this->id );

		// Only fired when not in admin.
		if ( ! papi_is_admin() ) {
			$value = papi_filter_format_value(
				$property->type,
				$value,
				$slug,
				$this->id,
				papi_get_meta_type()
			);
		}

		// Modify value before it's return to the theme via a defined format callback on the property.
		if ( ! papi_is_admin() && is_callable( $property->format_cb ) ) {
			$value = call_user_func( $property->format_cb, $value );
		}

		// Remove empty values from arrays.
		if ( is_array( $value ) ) {
			foreach ( $value as $index => $val ) {
				if ( papi_is_empty( $val ) ) {
					unset( $value[$index] );
				}
			}
		}

		return $value;
	}
Format property value from the property.

@param  string $slug
@param  mixed  $value

@return mixed