[#1026] Is this a bug? — Dave Thomas <Dave@...>
18 messages
2000/01/03
[#1053] rand() / drand48() — ts <decoux@...>
11 messages
2000/01/05
[#1055] Re: rand() / drand48()
— matz@... (Yukihiro Matsumoto)
2000/01/05
[#1061] Re: rand() / drand48()
— gotoken@... (GOTO Kentaro)
2000/01/07
Hi,
[#1067] Here docs not skipping leading spaces — Dave Thomas <Dave@...>
5 messages
2000/01/08
[#1083] YADQ (Yet Another Dumb Question) — Dave Thomas <Dave@...>
12 messages
2000/01/10
[#1084] Infinite loop — Dave Thomas <Dave@...>
17 messages
2000/01/11
[#1104] The value of while... — Dave Thomas <Dave@...>
24 messages
2000/01/11
[#1114] Re: The value of while...
— Dave Thomas <Dave@...>
2000/01/12
matz@netlab.co.jp (Yukihiro Matsumoto) writes:
[#1128] Re: The value of while... — David Suarez de Lis <excalibor@...>
Hi all,
1 message
2000/01/12
[#1133] Re: Class variables... — David Suarez de Lis <excalibor@...>
Hi there,
2 messages
2000/01/12
[#1158] Is this expected behavior? — Dave Thomas <Dave@...>
6 messages
2000/01/21
[#1172] Re: Possible bug in ruby-man-1.4 — Huayin Wang <wang@...>
> |Well, I guess it comes down to what you mean by an integer
10 messages
2000/01/24
[#1177] Re: Possible bug in ruby-man-1.4
— Dave Thomas <Dave@...>
2000/01/25
matz@netlab.co.jp (Yukihiro Matsumoto) writes:
[#1188] Enumerable and index — Dave Thomas <Dave@...>
5 messages
2000/01/27
[#1193] Semantics of chomp/chop — Dave Thomas <Dave@...>
7 messages
2000/01/28
[#1197] Question about 'open' — Dave Thomas <Dave@...>
8 messages
2000/01/30
[ruby-talk:01184] Re: Possible bug in ruby-man-1.4
From:
gotoken@... (GOTO Kentaro)
Date:
2000-01-25 18:01:51 UTC
List:
ruby-talk #1184
Hi,
In message "[ruby-talk:01177] Re: Possible bug in ruby-man-1.4"
on 00/01/24, Dave Thomas <Dave@thomases.com> writes:
>Now there's a problem ;-(
>
>Maybe the answer is to get rid of the concept of negative numeric
>literals, so there's never any ambiguity as to whether -2 is a literal
>of a method call? Then, as an optimization, the parser could notice
><Fixnum>.-@ terminal pairs and replace them with a negated
>Fixnum. That way
>
> (-2)**2 would be parsed as **
> /\
> / \
> -@ 2:Fixnum
> /
> /
> 2:Fixnum
>
> and optimized into **
> /\
> / \
> -2:Fixnum 2:Fixnum
Intuitively, -2**2 represents the mathematical notation
2 2
-2 but not (-2)
so, -2**2 == -4 is a reasonable solution.
On the other hand, I also expect as follows:
# A [=] B (A [!=] B) stands for the syntactically (in)equality of A
# and B. And angles for syntactical grouping on RHS.
- DIGITS [=] -<DIGITS> [!=] <-DIGITS>
-?a.m [=] <-?a>.m [!=] <-<?a>>.m
-2.0.m [=] <-2.0>.m [!=] <-<2.0>>.m
-nondigit.m [=] - nondigit.x
[=] <-<nondigit>>.m
[!=] -<<nondigit>.m>
x -y [=] x - y [=] x-y [=] <x>-<y>
x- nondigits.m [=] x-nondigits.m
[=] x -nondigits.m
[=] x - nondigits.m
[=] <x>-<nondigits.m>
x op - 2.0 [=] <x>op-2.0 [=] <x>op<-2.0> [!=] <x>op<-<2.0>>
x op - y [=] <x>op-y [=] <x>op<-<y>>
a - b ** c [=] a-b**c [=] <a>-<<b>**<c>>
Sorry, I cannot summarize them.
-- gotoken