Reserved keywords
FunC reserves the following symbols and words. These cannot be used as identifiers.Symbols
+ - * /
% ? : ,
; ( ) [
] { } =
_ < > &
| ^ ~ ==
!= <= >= <=>
<< >> ~>> ^>>
~/ ^/ ~% ^%
/% += -= *=
/= ~/= ^/= %=
~%= ^%= <<= >>=
~>>= ^>>= &= |=
^= ->
Words
return var repeat do
while until try catch
if ifnot then else
elseif elseifnot int cell
slice builder cont tuple
type forall extern global
asm impure inline inline_ref
auto_apply method_id operator infix
infixl infixr const #pragma
#include
Built-ins
This section covers extra language constructs that are not part of the core but are still important for functionality. Although they could be implemented in stdlib.fc, keeping them as built-in features allows the FunC optimizer to work more efficiently. In addition, FunC does not allow the built-in names in this section to be used as identifiers. However, there is an exception: built-ins with non-symbolic names can be used as identifiers for local variables.Built-ins with symbolic names
_+_ _-_ -_ _*_
_/_ _~/_ _^/_ _%_
_~%_ _^%_ _/%_ _<<_
_>>_ _~>>_ _^>>_ _&_
_|_ _^_ ~_ ^_+=_
^_-=_ ^_*=_ ^_/=_ ^_~/=_
^_^/=_ ^_%=_ ^_~%=_ ^_^%=_
^_<<=_ ^_>>=_ ^_~>>=_ ^_^>>=_
^_&=_ ^_|=_ ^_^=_ _==_
_!=_ _<_ _>_ _<=_
_>=_ _<=>_
Built-ins with non-symbolic names
divmod ~divmod moddiv ~moddiv
muldiv muldivr muldivc muldivmod
true false nil Nil
null? throw throw_if throw_unless
throw_arg throw_arg_if throw_arg_unless load_int
load_uint preload_int preload_uint store_int
store_uint ~store_int ~store_uint load_bits
preload_bits int_at cell_at slice_at
tuple_at at touch ~touch
touch2 ~touch2 ~dump ~strdump
run_method0 run_method1 run_method2 run_method3
The description of each of these built-ins must be specified, together with an example of usage.
throw
throw emits an unconditional exception. throw takes only one argument—the error code—since it always triggers an exception.
throw_if
throw_if emits an exception only if the provided condition is true. It receives two arguments: the error code, which defines the exception type, and
the condition.
throw_unless
throw_unless emits an exception only if the provided condition is false. It receives two arguments: the error code, which defines the exception type, and
the condition.
throw_arg
throw_arg is an unconditional exception with a parameter. It is the parameterized version of throw.
The first argument is a parameter of any type, the second argument defines the error code, and the third argument is the condition.
throw_arg_if
Parameterized version of throw_if.
The first argument is a parameter of any type, the second argument defines the error code, and the third argument is the condition.
throw_arg_unless
Parameterized version of throw_unless.
The first argument is a parameter of any type, the second argument defines the error code, and the third argument is the condition.
~dump
~dump outputs a variable to the debug log.
~strdump
~strdump outputs a string to the debug log.
divmod
divmod takes two numbers as input and returns the quotient and remainder of their division.
muldiv
muldiv performs a multiply-then-divide operation.
It uses a 513-bit intermediate result to prevent overflow if the final result fits within 257 bits.
true
true is an alias for -1.
false
false is an alias for 0.
null?
null? checks if the given argument is null. In FunC, the value null belongs to the TVM type Null, which represents the absence of a value for certain atomic types.
See null values for details.
touch and ~touch
touch pushes a variable to the top of the stack. ~touch is identical to touch, but it is adapted for use in modifying syntax.
Link for modifying syntax is missing.
at
Function at returns the value of a tuple element at the specified position.