Unary logical NOT was already implemented earlier.
Logical AND OR are expressed via conditional expression:
* a && b -> a ? (b != 0) : 0
* a || b -> a ? 1 : (b != 0)
They work as expected in any expressions. For instance, having
`cond && f()`, f is called only if cond is true.
For primitive cases, like `a > 0 && b > 0`, Fift code is not optimal,
it could potentially be without IFs.
These are moments of future optimizations. For now, it's more than enough.
This is a very big change.
If FunC has `.methods()` and `~methods()`, Tolk has only dot,
one and only way to call a `.method()`.
A method may mutate an object, or may not.
It's a behavioral and semantic difference from FunC.
- `cs.loadInt(32)` modifies a slice and returns an integer
- `b.storeInt(x, 32)` modifies a builder
- `b = b.storeInt()` also works, since it not only modifies, but returns
- chained methods also work, they return `self`
- everything works exactly as expected, similar to JS
- no runtime overhead, exactly same Fift instructions
- custom methods are created with ease
- tilda `~` does not exist in Tolk at all
Since I've implemented AST, now I can drop forward declarations.
Instead, I traverse AST of all files and register global symbols
(functions, constants, global vars) as a separate step, in advance.
That's why, while converting AST to Expr/Op, all available symbols are
already registered.
This greatly simplifies "intermediate state" of yet unknown functions
and checking them afterward.
Redeclaration of local variables (inside the same scope)
is now also prohibited.
Now, the whole .tolk file can be loaded as AST tree and
then converted to Expr/Op.
This gives a great ability to implement AST transformations.
In the future, more and more code analysis will be moved out of legacy to AST-level.
Several related changes:
- stdlib.tolk is embedded into a distribution (deb package or tolk-js),
the user won't have to download it and store as a project file;
it's an important step to maintain correct language versioning
- stdlib.tolk is auto-included, that's why all its functions are
available out of the box
- strict includes: you can't use symbol `f` from another file
unless you've #include'd this file
- drop all C++ global variables holding compilation state,
merge them into a single struct CompilerState located at
compiler-state.h; for instance, stdlib filename is also there
A new lexer is noticeably faster and memory efficient
(although splitting a file to tokens is negligible in a whole pipeline).
But the purpose of rewriting lexer was not just to speed up,
but to allow writing code without spaces:
`2+2` is now 4, not a valid identifier as earlier.
The variety of symbols allowed in identifier has greatly reduced
and is now similar to other languages.
SrcLocation became 8 bytes on stack everywhere.
Command-line flags were also reworked:
- the input for Tolk compiler is only a single file now, it's parsed, and parsing continues while new #include are resolved
- flags like -A -P and so on are no more needed, actually
All changes from PR "FunC v0.5.0":
https://github.com/ton-blockchain/ton/pull/1026
Instead of developing FunC, we decided to fork it.
BTW, the first Tolk release will be v0.6,
a metaphor of FunC v0.5 that missed a chance to occur.
The Tolk Language will be positioned as "next-generation FunC".
It's literally a fork of a FunC compiler,
introducing familiar syntax similar to TypeScript,
but leaving all low-level optimizations untouched.
Note, that FunC sources are partially stored
in the parser/ folder (shared with TL/B).
In Tolk, nothing is shared.
Everything from parser/ is copied into tolk/ folder.
