Loop While (while)
About 1 min
while
)
Loop While (Loop until condition false
Description
while
loops until loops until condition is false.
Normally the conditional and executed code block are 2 separate parameters however you can call while
with just 1 parameter where the code block acts as both the conditional and the code to be ran.
Usage
Until true
while { condition } { code-block } -> <stdout>
while { code-block } -> <stdout>
Until false
!while { condition } { code-block } -> <stdout>
!while { code-block } -> <stdout>
Examples
With conditional block
while
$i is less then 5
» i=0; while { $i<5 } { i=$i+1; out $i }
1
2
3
4
5
Without conditional block
» i=0; while { i=$i+1; $i<5; out }
true
true
true
true
false
Until false
while
$i is NOT greater than or equal to 5
» i=0; !while { $i >= 5 } { $i += 1; out $i }
1
2
3
4
5
Detail
Meta values
Meta values are a JSON object stored as the variable $.
. The meta variable will get overwritten by any other block which invokes meta values. So if you wish to persist meta values across blocks you will need to reassign $.
, eg
%[1..3] -> foreach {
meta_parent = $.
%[7..9] -> foreach {
out "$(meta_parent.i): $.i"
}
}
The following meta values are defined:
i
: iteration number
Synonyms
while
!while
See Also
- Define Global (
global
): Define a global variable and set it's value - Define Variable (
set
): Define a variable (typically local) and set it's value - Error String (
err
): Print a line to the stderr - For Each In List (
foreach
): Iterate through an array - For Each In Map (
formap
): Iterate through a map or other collection of data - For Loop (
for
): A more familiar iteration loop to existing developers - Output String (
out
): Print a string to the stdout with a trailing new line character let
: Evaluate a mathematical function and assign to variable (deprecated)
This document was generated from builtins/core/structs/while_doc.yaml.