Allow constants names to start with digits

[jubianchi]

$ echo -n '2_OVER_314*2' | vendor/bin/hoa compiler:pp Arithmetic.pp 0 -s
# namespace token name token value offset
-------------------------------------------------------------------------------
0 default constant 2_OVER_314 0
1 default times * 10
2 default number 2 11
3 default EOF 12

[Hywan]

👍

[Hywan]

You can move the number token after the constant token to avoid 7A to be consumed as a number 7 and a constant A instead of the constant 7A.

[Hywan]

And this way you might remove \b.

[jubianchi]

i was wondering what the best solution was ;) I'll move the lines if you prefer :)

[Hywan]

It's better to move the line I guess.

[jubianchi]

@Hywan & @hoaproject/hoackers good for me, let me know if I have to change anything else.

[Metalaka]

Good for me if you have thought about this:

Constants starting with digits can looks like hexadecimal value, so 0X1A is it a constant or the decimal value 26 ?

With this grammar it's a constant since we don't recognize (yet?) hexa/binary values.

http://php.net/manual/en/language.types.integer.php
hexadecimal : 0[xX][0-9a-fA-F]+

[jubianchi]

@Metalaka fair point!

The question is do we plan to support hex. values ? (@Hywan)

If yes, we'll have to find a consistent way to handle them among constants and ids.

[jubianchi]

Here is what I can propose:

• \x1A for hex values,
• \0755 for octal values,
• \b010101 for binary values

I already patched the grammar and the arithmetic visitor:

diff --git c/Arithmetic.pp i/Arithmetic.pp
index 02cc0fe..b948e11 100644
--- c/Arithmetic.pp+++ i/Arithmetic.pp@@ -44,13 +44,16 @@
%token bracket_ \(
%token _bracket \)
%token comma ,
+%token hex \\x[0-9a-fA-F]++%token octal \\0[0-7]++%token binary \\b[01]+
%token constant [0-9_]*[A-Z_]+[A-Z0-9_]*
+%token id \w+
%token number (0|[1-9]\d*)(\.\d+)?([eE][\+\-]?\d+)?
%token plus \+
%token minus \-|−
%token times \*|×
%token div /|÷
-%token id \w+
expression:
primary() ( ::plus:: #addition expression() )?
@@ -73,7 +76,10 @@ term:
| function()
number:
- <number>+ <number>+ | <hex>+ | <octal>+ | <binary>
constant:
<constant>
diff --git c/Visitor/Arithmetic.php i/Visitor/Arithmetic.php
index a7da754..32d808f 100644
--- c/Visitor/Arithmetic.php+++ i/Visitor/Arithmetic.php@@ -255,6 +255,12 @@ class Arithmetic implements Visitor\Visit
}
} elseif ('id' === $element->getValueToken()) {
return $value;
+ } elseif ('binary' === $element->getValueToken()) {+ return bindec($value);+ } elseif ('hex' === $element->getValueToken()) {+ return hexdec($value);+ } elseif ('octal' === $element->getValueToken()) {+ return octdec($value);
} else {
$out = (float) $value;
}

I ran this through those tests:

echo -n '2_SQRT_314 * 2'| vendor/bin/hoa compiler:pp Arithmetic.pp 0 -s
echo -n '2xfoo * 2'| vendor/bin/hoa compiler:pp Arithmetic.pp 0 -s
echo -n '0XA * 2'| vendor/bin/hoa compiler:pp Arithmetic.pp 0 -s
echo -n '\x1A * 2'| vendor/bin/hoa compiler:pp Arithmetic.pp 0 -s
echo -n '\0755 * 2'| vendor/bin/hoa compiler:pp Arithmetic.pp 0 -s
echo -n '\b01001 * 2'| vendor/bin/hoa compiler:pp Arithmetic.pp 0 -s
echo -n '\b01001'| vendor/bin/hoa compiler:pp Arithmetic.pp 0 -c Hoa.Math.Visitor.Arithmetic -s
echo -n '\x1A'| vendor/bin/hoa compiler:pp Arithmetic.pp 0 -c Hoa.Math.Visitor.Arithmetic -s
echo -n '\0755'| vendor/bin/hoa compiler:pp Arithmetic.pp 0 -c Hoa.Math.Visitor.Arithmetic -s

P.S: I could easily open a third PR for this feature if we want this ;)

[jubianchi]

Could not resist opening the PR: #40 ;)

[Hywan]

Hehe, I am sorry but… this is a Maths library. Did you ever write an hexidecimal value in a Math equation :-p? Personally, no. Thoughts?

[jubianchi]

@Hywan maths are not only decimal. One may need to do binary computations and get a decimal result.

[Savageman]

I agreee with @jubianchi : Math is just a tool. Mathematicians will use the most appropriate paradigm to solve their problems, and decimal is not always the best tool to solve a problem.

As for syntax, PHP uses natively 0660 for octal, 0x1A for hexa and 0b01001 for binary. Since it's a PHP library it would make sense to use the same?

[Hywan]

So a number must be start by 0 and the problem will be solved. It sounds correct too, a lot of language does this.

[jubianchi]

let's close this one! (#41 (comment))