* clarify `parseHexInt`, `parseOctInt` docstring and exception msgs
* add `parseBinInt` based on `parseutil.parseBin` implementation
Adds a `parseBinInt`, which parses a binary integer string and returns
it as an integer. This is based on the implementation of
`parseutil.parseBin`, removing the unnecessary parts.
* add tests for all `parse(Hex|Oct|Bin)Int` procs
* replace `parse*Int` proc impls by call to parseutil procs
Replaces the `parse(Hex|Oct|Bin)Int` procedure implementation by calls
to the `parseutil` procs, which receive a mutable argument.
Has the main advantage that the empty string as well as a "prefix
only" string, e.g. "0x" counts as an invalid integer.
Also moves the `parseOctInt` proc further up in the file so that all
`parse` procs are below one another.
* replace `var L` by `let L` in `parse` procs
There's no reason for the usage of `var` here.
* add `maxLen` optional arg for `parseutil.parse(Oct|Bin)`
Plus small change to test cases.
* update changelog about `parse*Int` procs
* fix `rejectParse` template in `tstrutils`
* make sure only `s.len` chars are parsed, if `maxLen+start` > s.len
Fixes a previous bug in `parseHex` (and now affected `parseOct` and
`parseBin`), which allowed to set `start + maxLen` to be larger than
the strings length. This resulted in an out of bounds access.
* move `parse*Int` proc change to breaking changes, add double `