ArrowMacros
A Julia package providing the macros @↓, @↑, @⤓, @⤒, and @←.
Usage
using ArrowMacros@↓ and @↑ provide ExtractMacro-like features with UnPack-like syntax and speed:
mutable struct A
a
b
end
s = A(1, -1)
@↓ a, b ← abs(b) + 1 = s
# (a, b) == (1, 2)
a += 1
@↑ s = a, b ← 2b - 1
# (s.a, s.b) == (2, 3)@⤓ and @⤒ work like @↓ and @↑, but they search in the tree structure of the struct:
mutable struct B
c
d
end
s = A(1, B(2, [3, 4]))
@⤓ a, b ← c, c ← d[1] = s
# (a, b, c) == (1, 2, 3)
a += 1
@⤒ s = a, b ← 2b
# (s.a, s.b) == (2, 4)@← allows for a common syntax between in-place and standard functions:
f(b) = b
@← a = f(1) # a = f(1)
# a == 1
a = [0, 0]
g(a, b) = a .= b
@← a = g(1) # g(a, 1)
# a == [1, 1]
h!(a, b) = a .= b
@← a = h(2) # h!(a, 2)
# a == [2, 2]Timings
using ExtractMacro
using UnPack
using BenchmarkToolss = A(1, [2, 3])
@btime @↓ a, b = s
@btime @extract s : a b
@btime @unpack a, b = sjulia>
37.429 ns (0 allocations: 0 bytes)
60.720 ns (0 allocations: 0 bytes)
37.525 ns (0 allocations: 0 bytes)Installation
ArrowMacros is compatible with Julia v1.0 and above, and it can be installed by running
]add ArrowMacrosWhat's next
- Improve error messages.
- Allow for
@← a .= f(b...)