Commands
qrun [-debug] [-prof] <qlangSrcDir>
- qrun -debug
<gopSrcDir>: print debug information - qrun -prof
<gopSrcDir>: do profile and generate profile report
Error handling
We reinvent error handling specification in Go+. We call them ErrWrap expressions:
expr! // panic if err
expr? // return if err
expr?:defval // use defval if errHow to use them? Here is an example:
import (
"strconv"
)
func add(x, y string) (int, error) {
return strconv.Atoi(x)? + strconv.Atoi(y)?, nil
}
func addSafe(x, y string) int {
return strconv.Atoi(x)?:0 + strconv.Atoi(y)?:0
}
println(`add("100", "23"):`, add("100", "23")!)
sum, err := add("10", "abc")
println(`add("10", "abc"):`, sum, err)
println(`addSafe("10", "abc"):`, addSafe("10", "abc"))The output of this example is:
add("100", "23"): 123
add("10", "abc"): 0 strconv.Atoi: parsing "abc": invalid syntax
===> errors stack:
main.add("10", "abc")
/Users/xsw/goplus/tutorial/15-ErrWrap/err_wrap.gop:6 strconv.Atoi(y)?
addSafe("10", "abc"): 10
Compared to corresponding Go code, It is clear and more readable.
And the most interesting thing is, the return error contains the full error stack. When we got an error, it is very easy to position what the root cause is.
How these ErrWrap expressions work? See Error Handling for more information.