% String Interpolation Operator

Expands the one key place into the string.

{{ "hello $place " % { place: "world" } ; }}

Expands multiple key values into a string from a map.

{{ var mymap = { name : "john" , age : 20, favcolor : "red"}; 
"$name is $age" % mymap; }}

Expands based on a list

{{ "the $0 is $1" % ["date",date.now ]; }}