Difference between revisions of "Function toboolean()"
Jump to navigation
Jump to search
(Založena nová stránka s textem „{{DISPLAYTITLE:function toboolean()}} Converts variable to boolean (true or false) value (the only type usable in conditions). <i>boolean</i> toboolean(<…“) |
|||
| Line 2: | Line 2: | ||
Converts variable to boolean (true or false) value (the only type usable in conditions). | Converts variable to boolean (true or false) value (the only type usable in conditions). | ||
| − | <i>boolean</i> toboolean(< | + | <i>boolean</i> toboolean(<code>variable</code>) |
=== Parameters === | === Parameters === | ||
| − | <i>mixed</i> < | + | * <i>mixed</i> <code>variable</code> will be converted to boolean value. |
=== Return value === | === Return value === | ||
Revision as of 19:56, 18 April 2017
Converts variable to boolean (true or false) value (the only type usable in conditions).
boolean toboolean(variable)
Parameters
- mixed
variablewill be converted to boolean value.
Return value
Falsy values are:
- number 0
- boolean false
- string ""
- table {}
Anything else converts to true.
Usage
local answer = 42
if toboolean(answer) then
log("42 is true!")
else
log("42 is false!")
end
To use inverse conversion (boolean to number) use 'x and 1 or 0' idiom:
local x = true
logf("x is %d", x and 1 or 0)
See also
Lua system's tonumber() and tostring() functions.
