Repeat: Difference between revisions

=={{header|Nim}}==

<lang python>proc example =

echo "Example"

# Ordinary procedure

proc repeatProc(fn: proc, n: int) =

for x in 0..<n:

fn()

repeatProc(example, 4)

# Template (code substitution), simplest form of metaprogramming

# that Nim has

template repeatTmpl(n: int, body: untyped): untyped =

for x in 0..<n:

body

# This gets rewritten into a for loop

repeatTmpl 4:

example()

import std/macros

# A macro which takes some code block and returns code

# with that code block repeated n times. Macros run at

# compile-time

macro repeatMacro(n: static[int], body: untyped): untyped =

result = newStmtList()

for x in 0..<n:

result.add body

# This gets rewritten into 4 calls to example()

# at compile-time

repeatMacro 4:

example()

</lang>