SHELL

bash variable in string

${!var}	#Just use to use reference value inside another variable ;)

bash use variable in string

domain='http://www.whitehouse.gov'
path='/some/path'
base_url="$domain$path"

Example of Bash Variable in String

echo "***Assigning a variable***"
Var_1="Softhunt"
echo "***Printing Var_1 which is assigned value of Softhunt.net***"
echo $Var_1
echo "***Printing Var_2 which is not assigned***"
echo "***Nothing gets printed!***"
Var_start="https://www."
Var_end=".net"
echo $Var_start$Var_1$Var_end
echo "***Sequence keyword will print 1 to 4 in different lines***"
seq 1 4
echo "***The following command will print it in single line***"
echo $(seq 1 4)
echo "***Arthmetical operator to add 2 numbers entered by users: 2 and 3"
echo $((2+3))
echo "***Using bc utility to restrict the number of decimals***"
echo "7.5 / 2.1" | bc
echo "***Using bc utility to not restrict the number of decimals***"
echo "7.5 / 2.1" | bc -l