Difference between revisions of "Assert"

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=== Description ===
 
=== Description ===
Issues an error when the value of its argument ''v'' is false (i.e., nil or false), otherwise returns all its arguments.
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Issues an error when the value of its argument ''v'' is false (i.e.: nil or false), otherwise returns all its arguments.
 
<source lang="lua">
 
<source lang="lua">
 
assert(v,message)
 
assert(v,message)

Latest revision as of 10:01, 2 March 2021

Available since: Gideros 2011.6
Class: (global)

Description

Issues an error when the value of its argument v is false (i.e.: nil or false), otherwise returns all its arguments.

assert(v,message)

message is an error message, when absent it defaults to "assertion failed!".

Parameters

v: (any) expression/function to assert
message: (string) error message if assert fails optional

Example

Checks if a texture is valid

function isValidTexture()
	local result, msg = assert(Texture.new(texturepath), "file is not recognised")
	print(result, msg)
	return result
end

function showTexture()
	if isValidTexture() then bmp = Bitmap.new(Texture.new(texturepath)) end
end