kinds¶
The kind member selects the kind of a given type.
Declaration¶
Syntax¶
Integer
Real
Complex
Character
Logical
kind
Arguments¶
None.
Return values¶
None.
Description¶
kind denotes the kind of a given type. LFortran supports the following:
Integer kinds: 1 (i8), 2 (i16), 4 (i32), 8 (i64)
Real kinds: 4 (f32), 8 (f64)
Complex kinds: 4 (c32), 8 (c64)
Character kinds: 1 (utf8 string)
Logical kinds: 1, 2, 4: (boolean represented by 1, 2, 4 bytes; the default kind is 4, just like the default integer kind, consistent with Python and Fortran: in Python "Booleans in Python are implemented as a subclass of integers", in Fortran the "default logical kind has the same storage size as the default integer"; we currently use kind=4 as default integer, so we also use kind=4 for the default logical.)
Types¶
LFortan supports the following types:
Integer kinds
Real kinds
Complex kinds
Character kinds
Logical kinds
Examples¶
program const_kind_01
integer, parameter :: sp = 4, dp = 8
real(sp), parameter :: r1 = 1.0_sp
real(dp), parameter :: r2 = 1.0_dp
real :: r3
r3 = 1.0_sp
r3 = 1.0_dp
print *, sp, dp, r1, r2, r3
end program
ASR:
(TranslationUnit
(SymbolTable
1
{
const_kind_01:
(Program
(SymbolTable
2
{
dp:
(Variable
2
dp
Local
(IntegerConstant 8 (Integer 4 []))
(IntegerConstant 8 (Integer 4 []))
Parameter
(Integer 4 [])
Source
Public
Required
.false.
),
r1:
(Variable
2
r1
Local
(RealConstant
1.000000
(Real 4 [])
)
(RealConstant
1.000000
(Real 4 [])
)
Parameter
(Real 4 [])
Source
Public
Required
.false.
),
r2:
(Variable
2
r2
Local
(RealConstant
1.000000
(Real 8 [])
)
(RealConstant
1.000000
(Real 8 [])
)
Parameter
(Real 8 [])
Source
Public
Required
.false.
),
r3:
(Variable
2
r3
Local
()
()
Default
(Real 4 [])
Source
Public
Required
.false.
),
sp:
(Variable
2
sp
Local
(IntegerConstant 4 (Integer 4 []))
(IntegerConstant 4 (Integer 4 []))
Parameter
(Integer 4 [])
Source
Public
Required
.false.
)
})
const_kind_01
[]
[(=
(Var 2 r3)
(RealConstant
1.000000
(Real 4 [])
)
()
)
(=
(Var 2 r3)
(Cast
(RealConstant
1.000000
(Real 8 [])
)
RealToReal
(Real 4 [])
(RealConstant
1.000000
(Real 4 [])
)
)
()
)
(Print
()
[(Var 2 sp)
(Var 2 dp)
(Var 2 r1)
(Var 2 r2)
(Var 2 r3)]
()
()
)]
)
})
[]
)