Logicandcompare (#50)

* TokenFactory: allowing multicharacter tokens

* Added logical and compare operators: <, <=, >, >=, ==, !=, ||, &&

* Fixed operator priorities

* Error messages fixes

* Fixed operators priority

The priorities are assigned by following the php language standard
(https://www.php.net/manual/en/language.operators.precedence.php)
I've assigned precedence in steps of 10 units by following the linked page:
230 clone new
220 **
210 ++ -- ~ (int) (float) (string) (array) (object) (bool) @
200 instanceof
190 !
180 * / %
170 + - .
160 << >>
150 < <= > >=
140 == != === !== <> <=>
130 &
120 ^
110 |
100 &&
 90 ||
 80 ??
 70 ? :
 60 = += -= *= **= /= .= %= &= |= ^= <<= >>=
 50 yield from
 40 yield
 30 and
 20 xor
 10 or

* Added if() function

* Cache key fix

There are cases where the cache key creation raised an error, for example
while evaluating the expression "if(cos(2), cos(2), 0)", because the
if() function was passing a float to the MathExecutor:execute() method.

1 files changed, 1 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
index c3b38ab..7256f68 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@ vendor/
 .idea/
 composer.lock
 .phpunit.result.cache
+.vscode