protected void pushOnExpressionStackLengthStack(int pos) {

	int stackLength = this.expressionLengthStack.length;
	if (++this.expressionLengthPtr >= stackLength) {
		System.arraycopy(
			this.expressionLengthStack, 0,
			this.expressionLengthStack = new int[stackLength + StackIncrement], 0,
			stackLength);
	}
	this.expressionLengthStack[this.expressionLengthPtr] = pos;
}