-eq unary operator expected - bash

Question

I have this code here.
But I get the error:
./concatconvert: line 9: [: -eq: unary operator expected
./concatconvert: line 18: [: -eq: unary operator expected
This is my code:
#!/bin/bash
param=$#
if [ $# -le 2 ]
then
echo "Usage: concatconvert [-u|-1] FILE ...
Description: concatenates FILE(s) to standard output separating them with divider -----. Optional first argument -u or -l converts contents to uppercase or lowercase,$
fi
if [ $1 -eq "-u" ]
then
while [ $param -ge 1 ]
do
./concat | awk '{print toupper($0)}'
param=$(( param-1 ))
shift
done
fi
if [ $1 -eq "-l" ]
then
while [ $param -ge 1 ]
do
./concat | awk '{print tolower($0)}'
param=$(( param-1 ))
shift
done
fi
Why am I getting this error? I thought that -eq is a unary operator?

Answer 1

You have missed few things eg--> " for echo command was NOT closed. Then in if condition since you are comparing a string so change it to if [[ "$1" = "-u" ]] so following could be the script(I haven't tested it since no samples were there).
#!/bin/bash
param=$#
if [ $# -le 2 ]
then
echo "Usage: concatconvert [-u|-1] FILE ...
Description: concatenates FILE(s) to standard output separating them with divider -----. Optional first argument -u or -l converts contents to uppercase or lowercase,$"
fi
if [[ "$1" = "-u" ]]
then
while [ $param -ge 1 ]
do
./concat | awk '{print toupper($0)}'
param=$(( param-1 ))
shift
done
fi
if [[ $1 -eq -l ]]
then
while [ $param -ge 1 ]
do
./concat | awk '{print tolower($0)}'
param=$(( param-1 ))
shift
done
fi