scenario array-from-args [
run [
local-scope
x:&:@:num <- new-array 0, 1, 2
10:@:num/raw <- copy *x
]
memory-should-contain [
10 <- 3 # array length
11 <- 0
12 <- 1
13 <- 2
]
]
# create an array out of a list of args
def new-array -> result:&:@:_elem [
local-scope
capacity:num <- copy 0
{
# while read curr-value
curr-value:_elem, exists?:bool <- next-input
break-unless exists?
capacity <- add capacity, 1
loop
}
result <- new _elem:type, capacity
rewind-inputs
i:num <- copy 0
{
# while read curr-value
done?:bool <- greater-or-equal i, capacity
break-if done?
curr-value:_elem, exists?:bool <- next-input
assert exists?, [error in rewinding inputs to new-array]
*result <- put-index *result, i, curr-value
i <- add i, 1
loop
}
return result
]
# fill an existing array with a set of numbers
# (contributed by Caleb Couch)
def fill array:&:@:num -> array:&:@:num [
local-scope
load-inputs
loopn:num <- copy 0
length:num <- length *array
{
length?:bool <- equal loopn, length
break-if length?
object:num, arg-received?:bool <- next-input
break-unless arg-received?
*array <- put-index *array, loopn, object
loopn <- add loopn, 1
loop
}
]
scenario fill-on-an-empty-array [
local-scope
array:&:@:num <- new number:type, 3
run [
array <- fill array, 1 2 3
10:@:num/raw <- copy *array
]
memory-should-contain [
10 <- 3
11 <- 1
12 <- 2
13 <- 3
]
]
scenario fill-overwrites-existing-values [
local-scope
array:&:@:num <- new number:type, 3
*array <- put-index *array, 0, 4
run [
array <- fill array, 1 2 3
10:@:num/raw <- copy *array
]
memory-should-contain [
10 <- 3
11 <- 1
12 <- 2
13 <- 3
]
]
scenario fill-exits-gracefully-when-given-no-inputs [
local-scope
array:&:@:num <- new number:type, 3
run [
array <- fill array
10:@:num/raw <- copy *array
]
memory-should-contain [
10 <- 3
11 <- 0
12 <- 0
13 <- 0
]
]
# swap two elements of an array
# (contributed by Caleb Couch)
def swap array:&:@:num, index1:num, index2:num -> array:&:@:num [
local-scope
load-inputs
object1:num <- index *array, index1
object2:num <- index *array, index2
*array <- put-index *array, index1, object2
*array <- put-index *array, index2, object1
]
scenario swap-works [
local-scope
array:&:@:num <- new number:type, 4
array <- fill array, 4 3 2 1
run [
array <- swap array, 0, 2
10:num/raw <- index *array, 0
11:num/raw <- index *array, 2
]
memory-should-contain [
10 <- 2
11 <- 4
]
]
# reverse the elements of an array
# (contributed by Caleb Couch)
def reverse array:&:@:_elem -> array:&:@:_elem [
local-scope
load-inputs
start:num <- copy 0
length:num <- length *array
end:num <- subtract length, 1
{
done?:bool <- greater-or-equal start, end
break-if done?
array <- swap array, start, end
start <- add start, 1
end <- subtract end, 1
loop
}
]
scenario reverse-array-odd-length [
local-scope
array:&:@:num <- new number:type, 3
array <- fill array, 3 2 1
run [
array <- reverse array
10:@:num/raw <- copy *array
]
memory-should-contain [
10 <- 3
11 <- 1
12 <- 2
13 <- 3
]
]
scenario reverse-array-even-length [
local-scope
array:&:@:num <- new number:type, 4
array <- fill array, 4 3 2 1
run [
array <- reverse array
10:@:num/raw <- copy *array
]
memory-should-contain [
10 <- 4
11 <- 1
12 <- 2
13 <- 3
14 <- 4
]
]