[M3devel] Interpretation of numbers

[Dariusz Knociński]

Hi all,

in my spare time I write a lexer to Modula-3 for Scintilla library and I found 
mistake in numeric constants with explicitly given base number system, eg. octal
numbers.

This simple program in C generates compiler error:

#include <stdio.h>

int main( void )
{
	unsigned o;
	
	o = 0787;
	
	printf( "o = %u\n", o );
	
	return 0;
}

in gcc 4.5.1 20100924 (Red Hat 4.5.1-4) this is:

Numbers.c: In function ‘main’:
Numbers.c:7:6: error: invalid digit "8" in octal constant

but CM3 with analogical program:

MODULE Numbers EXPORTS Main;

IMPORT IO, Fmt;

VAR
	o : CARDINAL;
	
BEGIN

	o := 8_787;
	
	IO.Put( "o = 8_" & Fmt.Unsigned( o, 8 ) & "\n" );
	
END Numbers.

compiles his properly and the program generate output:

o = 8_1007

This is correct number, 519 decimal, but similar mistakes can be difficult to find.

Best regards
Dariusz Knociński.