Difference between revisions of "For"

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m (Replaced old <LSL> block with <source lang="lsl2">)
(8 intermediate revisions by 6 users not shown)
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|spec
|spec
|caveats
|caveats
|examples=<pre>//single statement type.
|examples=<source lang="lsl2">
integer a = 0;
//single statement type.
integer a;
integer b = 10;
integer b = 10;
for(; a < b; ++a)
for(a = 1; a <= b; ++a)
     llOwnerSay((string)a);
     llOwnerSay((string)a);
</pre>
</source>
<pre>//block statement
<source lang="lsl2">
//block statement
integer a = 0;
integer a = 0;
integer b = 10;
integer b = 10;
Line 25: Line 27:
     llOwnerSay((string)a);
     llOwnerSay((string)a);
}
}
</pre>
</source>
<pre>//null statement
<source lang="lsl2">
//null statement
integer a = 0;
integer a = 0;
integer b = 10;
integer b = 10;
for(; a < b; llOwnerSay((string)(a++)));
for(; a < b; llOwnerSay((string)(a++)));
</pre>
</source>
|helpers
|helpers
|also_header
|also_header
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|also_footer
|also_footer
|notes=A for loop is the same as a while loop as below.
|notes=A for loop is the same as a while loop as below.
<pre>
<source lang="lsl2">
initializer;
initializer;
while(condition);
while(condition)
{
{
     loop;
     loop;
     increment;
     increment;
}
}
</pre>
</source>
|mode
|mode
|deprecated
|deprecated
|cat1=Conditional
|cat1=Flow Control/Loop
|cat2
|cat2=Conditional
|cat3
|cat3
|cat4
|cat4
}}
}}

Revision as of 02:05, 22 January 2015

for( initializer; condition; incrementloop

•  initializer Executed once just before checking condition.
•  condition If this executes as true then loop is executed.
•  increment Executed after loop, then condition is checked again.
•  loop Can be either a single statement, a block statement, or a null statement.


Any of the statements can be null statements.

Specification

Conditional Types
Type Condition
integer True if it is not zero.
float True if it is not zero.[1]
string True if its length is not zero.
key True only if it is a valid key and not NULL_KEY.
vector True if the vector is not ZERO_VECTOR.
rotation True if the rotation is not ZERO_ROTATION.
list True if the length is not zero. Note that correct behavior is only seen with Mono-compiled scripts; LSO-compiled scripts incorrectly resolve to false if the list is non-empty: BUG-230728

Examples

//single statement type.
integer a;
integer b = 10;
for(a = 1; a <= b; ++a)
    llOwnerSay((string)a);
//block statement
integer a = 0;
integer b = 10;
for(; a < b; ++a)
{
    llOwnerSay((string)a);
    llOwnerSay((string)a);
}
//null statement
integer a = 0;
integer b = 10;
for(; a < b; llOwnerSay((string)(a++)));

Notes

A for loop is the same as a while loop as below.

initializer;
while(condition)
{
    loop;
    increment;
}

Deep Notes

Search JIRA for related Issues

Footnotes

  1. ^ The OpenSim LSL compiler will not do this implicitly. You will need to use an explicit check.