Install and compile Objective-C in linux

setup.sh

function _print(){
    echo `date`":" $1 "..."
}

_print "Installing gcc compiler for objective C"

sudo apt-get install gnustep gnustep-devel gobjc tree

_print "Creating a sample test project structure"

sample_dir="/tmp/iOS-Test-Project"
sample_file="main.m"
output_file="main"
install_dir="~/bin"
script_file="compileAndRunObjC"

mkdir -p $sample_dir && cd $sample_dir

echo '#import <Foundation/Foundation.h>' > $sample_file
echo 'int main(int argc, char const *argv[]){' >> $sample_file
echo '  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];' >> $sample_file
echo '  NSLog(@"<YO...Objective-C successfuly compiled in Linux :)>");' >> $sample_file
echo '  [pool drain];' >> $sample_file
echo '  return 0;' >> $sample_file
echo '}' >> $sample_file

_print "Added code to $sample_file in iOS-Testing-Project"
_print "Compiling $sample_file"

gcc `gnustep-config --objc-flags` -o $output_file $sample_file -L /GNUstep/System/Library/Libraries -lobjc -lgnustep-base
./$output_file  # execute the compiled code
tree $sample_dir

_print "Adding 'compileAndRunObjc' to your system for easy compilation"

mkdir $install_dir && cd $install_dir
echo "gcc `gnustep-config --objc-flags` -o $1 $1.m -L /GNUstep/System/Library/Libraries -lobjc -lgnustep-base\n./$1" > $script_file
chmod $script_file
echo "export PATH=$HOME/scripts:$PATH" >> ~/.bashrc

source ~/.bashrc
tree $install_dir

echo 'Following things have been added to your system:'
echo 't1> gnustep'
echo 't2> gobjc'
echo "t3> $script_file"
echo 'Use "compileAndRunObjC <file-name-without-dot-m>" to compile and run your objective c code'

Im getting this error:
compileAndRunObj: command not found
what can i do to fix it...