while loop definition programming
construct, found in nearly all procedural languages, that executes one or more instructions (the "loop body") repeatedly so long as some condition
evaluates to true. In contrast to a repeat loop
, the loop body will not be executed at all if the condition is false on entry to the while.
For example, in C
, a while loop is written
while () ;
where is any expression and is any statement, including a compound statement within braces "..".
A for loop, e.g. in the C language, extends the while loop syntax to collect pre-loop initialisation and loop-end logic into the beginning of the statement.
Perl provides the "until" loop that loops until the loop condition is true.