go get github.com/antonmedv/expr/cmd/exePrint ast of program.
echo '1 + 2' | exe -astDisassemble bytecode to human readable format.
echo 'map(0..9, {# * 2})' | exe -bytecodeRun expression.
echo '2**8' | exe -runStart interactive debugger.
echo 'all(1..3, {# > 0})' | exe -debug