First class environments: Difference between revisions

=={{header|Nim}}==

{{trans|C}}

<lang Nim>import strformat

const Jobs = 12

type Environment = object

sequence: int

count: int

var

env: array[Jobs, Environment]

sequence, count: ptr int

#---------------------------------------------------------------------------------------------------

proc hail() =

stdout.write fmt"{sequence[]: 4d}"

if sequence[] == 1: return

inc count[]

sequence[] = if (sequence[] and 1) != 0: 3 * sequence[] + 1

else: sequence[] div 2

#---------------------------------------------------------------------------------------------------

proc switchTo(id: int) =

sequence = addr(env[id].sequence)

count = addr(env[id].count)

#---------------------------------------------------------------------------------------------------

template forAllJobs(statements: untyped): untyped =

for i in 0..<Jobs:

switchTo(i)

statements

#———————————————————————————————————————————————————————————————————————————————————————————————————

for i in 0..<Jobs:

switchTo(i)

env[i].sequence = i + 1

var terminated = false

while not terminated:

forAllJobs:

hail()

echo ""

terminated = true

forAllJobs:

if sequence[] != 1:

terminated = false

break

echo ""

echo "Counts:"

forAllJobs:

stdout.write fmt"{count[]: 4d}"

echo ""</lang>

{{out}}

<pre> 1 2 3 4 5 6 7 8 9 10 11 12

1 1 10 2 16 3 22 4 28 5 34 6

1 1 5 1 8 10 11 2 14 16 17 3

1 1 16 1 4 5 34 1 7 8 52 10

1 1 8 1 2 16 17 1 22 4 26 5

1 1 4 1 1 8 52 1 11 2 13 16

1 1 2 1 1 4 26 1 34 1 40 8

1 1 1 1 1 2 13 1 17 1 20 4

1 1 1 1 1 1 40 1 52 1 10 2

1 1 1 1 1 1 20 1 26 1 5 1

1 1 1 1 1 1 10 1 13 1 16 1

1 1 1 1 1 1 5 1 40 1 8 1

1 1 1 1 1 1 16 1 20 1 4 1

1 1 1 1 1 1 8 1 10 1 2 1

1 1 1 1 1 1 4 1 5 1 1 1

1 1 1 1 1 1 2 1 16 1 1 1

1 1 1 1 1 1 1 1 8 1 1 1

1 1 1 1 1 1 1 1 4 1 1 1

1 1 1 1 1 1 1 1 2 1 1 1

Counts:

0 1 7 2 5 8 16 3 19 6 14 9</pre>