Control Structures: Difference between revisions
imported>Aqualectrix added a section on break/continue, mostly to note that they exist |
imported>Aqualectrix added switch statement syntax, ripped from r7098 and r7100 commit logs |
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Line 11: | Line 11: | ||
{} | {} | ||
== switch == | |||
switch (value) | |||
{ | |||
case expression: | |||
statement | |||
statement | |||
... | |||
break; | |||
default: | |||
statement | |||
statement | |||
... | |||
break; | |||
} | |||
== while == | == while == | ||
Line 60: | Line 75: | ||
See http://kolmafia.sourceforge.net/advanced.html#maps for more details on maps. | See http://kolmafia.sourceforge.net/advanced.html#maps for more details on maps. | ||
== continue/break == | == continue/break == | ||
Like many languages with looping structures, ASH supports the break and continue statements. All looping structures (for, while, repeat until, and foreach) support these | Like many languages with looping structures, ASH supports the break and continue statements. All looping structures (for, while, repeat until, and foreach) support these statements. | ||
break; | break; | ||
Breaks out of the smallest enclosing loop. | Breaks out of the smallest enclosing loop. In a switch statement, breaks out of the switch statement. Execution resumes at the first statement after the end of the loop/switch statement. | ||
continue; | continue; | ||
Continues on to the next iteration of the loop (skipping any statments in this iteration that occur after the continue | Continues on to the next iteration of the loop (skipping any statments in this iteration that occur after the continue statement). In a switch statement, continue is allowed iff the switch is inside a loop, and acts as any other continue. |
Revision as of 05:39, 18 November 2009
if/else
if (boolean)
{}
else if (boolean)
{}
else
{}
switch
switch (value) { case expression: statement statement ... break; default: statement statement ... break; }
while
while (boolean)
{}
repeat until
repeat {} until (boolean);
for
for x from a to b by c
is the general case. You don't need to specify whether it's going up or down - although doing so by using upto or downto does allow a runtime check to make sure you didn't screw up.
If you don't specify "c", it defaults to incrementing/decrementing by 1. The first iteration is at a and the last is at b (that is to say, it goes from a to b, inclusive).
foreach
foreach x in map
{}
"map" must be an aggregate - a map or a slice. x takes on each value of the map index in turn. If there is more than one index, x iterates over the first index.
For example:
boolean [int][string] map; map[15]["test"] = true; foreach int_index in map { print(int_index); //this will print '15' once, since there is only one valid value for this index foreach string_index in map[int_index] //this iterates over the "slice" of the map where 1 is fixed as the index { print(string_index); //This will print "test" once, since there is only one valid value for this index print(map[int_index][string_index]); //this will print "true" } }
So the output is
15 test true
Note that instead of nesting foreach statements, for a multidimensional map, two iterators can be used inline.
foreach x,y in map
is identical to
foreach x in map { foreach y in map[x] }
See http://kolmafia.sourceforge.net/advanced.html#maps for more details on maps.
continue/break
Like many languages with looping structures, ASH supports the break and continue statements. All looping structures (for, while, repeat until, and foreach) support these statements.
break;
Breaks out of the smallest enclosing loop. In a switch statement, breaks out of the switch statement. Execution resumes at the first statement after the end of the loop/switch statement.
continue;
Continues on to the next iteration of the loop (skipping any statments in this iteration that occur after the continue statement). In a switch statement, continue is allowed iff the switch is inside a loop, and acts as any other continue.