erg/tests/should_err/subtyping.er
2023-06-06 00:04:18 +09:00

78 lines
1.4 KiB
Python

f(x: Nat): Int = x
y: Ratio = f 1
# Erg's type checking does not necessarily enlarge the type. So this is OK.
z: Int = y
# But this is invalid.
invalid: 10..<20 = z #ERR
for! [(1, 2)], ((i, j),) =>
k = i + 1 # OK
print! k
for! [(1, 2)], ((i, j),) =>
k = i + "a" # ERR
print! k
for! zip([1], ["a"]), ((i: Int, s: Str),) =>
k = i + 1
l = s + "b"
print! k, l
# ERR: i should be Int
for! zip([1], ["a"]), ((i: Str, s: Str),) =>
k = i + "a"
print! k
for! zip([1], ["a"]), ((i, s),) =>
k = i + "a" # ERR
print! k
for! zip([1+1], ["a"+"b"]), ((i, s),) => # i: Nat, s: Str
print! i + 1
print! s + "b"
print! s + 1 # ERR
print! i + "a" # ERR
for! "aaa", a =>
print! a # OK
for! "aaa", a =>
print! a + 1 # ERR
inty|T :> Nat, T <: Int|(x: T) = x + x
inty 0 # OK
inty 1.1 # ERR
# g: |T <: Ord and Eq and Show| T -> T
g x =
_ = x <= x
_ = x == x
_ = x.to_str()
x
g 1 # OK
g None # ERR
h x, y =
_ = x == y
_ = x - y
x + y
_ = h -1, -2 # OK
_ = h 1, 2 # OK
_ = h "a", "b" # ERR
i|T|(x: T): T =
_: Int = x
x + "a" # ERR
i2|T|(x: T): T =
x + "a"
_ = i 1
_ = i2 1 # ERR
_: Array!({"a", "b"}, 2) = !["a", "b"] # OK
_: Array!({"a", "b", "c"}, 2) = !["a", "b"] # OK
_: Array!({"a", "c"}, 2) = !["a", "b"] # ERR
_: Array!({"a"}, 2) = !["a", "b"] # ERR
ii _: Iterable(Iterable(Str)) = None
ii [1] # ERR
ii [[1]] # ERR
ii [["a"]]
ii ["aaa"] # Str <: Iterable Str