[cast]
Description
This is a shortcut to programmatically re-cast an element to a new type.
Parameters
-in
custom type, required The element to re-cast.
-as
string, required The target type.
Sample Usage
// testing
var('types') = array(
'array',
'boolean',
'bytes',
'date',
'decimal',
'duration',
'integer',
'map',
'pair',
'string',
);
iterate($types, local('t'));
var('foo' = '2');
cast($foo, -as=#t);
$foo + ': ' + $foo->type;
'<br>\n';
/iterate;
'<hr>\n';
var('bar' = '<?xml version="1.0"?><root><record>hi</record></root>');
$bar->type;
'<br>\n';
cast($bar, -as='xml');
$bar->type;
Source Code
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including the complete documentation and sample usage shown
on this page. Place the downloaded ".inc" file in your
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tag immediately.
1
define_tag(
'cast',
-required='in',
-required='as',
-priority='replace',
-description='Casts the given object as the given type.'
);
protect;
if(#as == 'bytes');
local('x' = bytes);
#x->importstring(string(#in));
#in = #x;
else;
#in = tags->find(#as)->run(
-params=array(#in)
);
/if;
/protect;
/define_tag;
Related Tags
Comments
Using Cast to dynamically assign and execute types and methods.
[// lasso define_tag( 'cast', -required='in', -required='as', -priority='replace', -description='Casts the given object as the given type.' ); protect; if(#as == 'bytes'); local('x' = bytes); #x->importstring(string(#in)); #in = #x; else; #in = tags->find(#as)->run( -params=array(#in) ); /if; /protect; /define_tag; define_type:'test'; local('do')=string; define_tag('onCreate'); self->'do'='monster'; /define_tag; define_tag:'print', -required='str'; var:'y' = ' it works'; return('string input: ' + #str + ' property input: '+self->'do'); /define_tag; define_tag('_unknowntag', -encodenone ); return(tag_name); /define_tag; define_tag('three', -encodenone ); return(self->'do'); /define_tag; /define_type; var('once'='test'); var:'x' = $once; /* $x->type; $once->type; */ $x->type; '
\n'; cast($x, -as=$once); $x->type; '
\n'; var:'object' = $x; var:'method' = 'three'; ($object)->\$method->(run( -owner=$object )); ]