Editing Module:Yesno/doc (section)

===Handling nil results===
By definition:
<syntaxhighlight lang="lua">
yesno(nil)         -- Returns nil.
yesno('foo')       -- Returns nil.
yesno(nil, true)   -- Returns nil.
yesno(nil, false)  -- Returns nil.
yesno('foo', true) -- Returns true.
</syntaxhighlight>

To get the binary <syntaxhighlight lang="lua" inline>true/false</syntaxhighlight>-only values, use code like:
<syntaxhighlight lang="lua">
myvariable = yesno(value or false) -- When value is nil, result is false.
myvariable = yesno(value or true)  -- When value is nil, result is true. (XXX: when value is false, result is true...)
myvariable = yesno('foo') or false  -- Unknown string returns nil, result is false.
myvariable = yesno('foo', true) or false  -- Default value (here: true) applies, result is true.
</syntaxhighlight>

Better suggestions:
<syntaxhighlight lang="lua">
local myvariable = yesno(value)
if myvariable == nil then -- value is nil or an unrecognized string
    myvariable = true
end

-- more efficient when value is nil, but more verbose
-- (note the default result has to be written twice)
local myvariable
if value == nil then
    myvariable = true
else
    myvariable = yesno(value, true)
end
</syntaxhighlight><!--

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