Grainfmt: Comment lost when preceding a number

[marcusroberts]

If I write a bizzare comment like this

print(/*a*/ 1 /*b*/)

The first comment is lost after formatting

print(1 /*b*/)

This is happening because the location of the argument is wrong (says @ospencer )

[ospencer]

In particular, this issue is specific to positive numbers. The way we check for the dash of a negative number results in an incorrect location for the argument (but not the actual number itself).