This CL introduces compiler support for the new binary and octal integer
literals, hexadecimal floats, and digit separators for all number literals.
The new Go 2 number literal scanner accepts the following liberal format:
number = [ prefix ] digits [ "." digits ] [ exponent ] [ "i" ] .
prefix = "0" [ "b" |"B" | "o" | "O" | "x" | "X" ] .
digits = { digit | "_" } .
exponent = ( "e" | "E" | "p" | "P" ) [ "+" | "-" ] digits .
If the number starts with "0x" or "0X", digit is any hexadecimal digit;
otherwise, digit is any decimal digit. If the accepted number is not valid,
errors are reported accordingly.
See the new test cases in scanner_test.go for a selection of valid and
invalid numbers and the respective error messages.
R=Go1.13
Updates #12711.
Updates #19308.
Updates #28493.
Updates #29008.
Change-Id: Ic8febc7bd4dc5186b16a8c8897691e81125cf0ca
Reviewed-on: https://go-review.googlesource.com/c/157677
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Robert Griesemer