Difference between revisions of "Assert"

From GiderosMobile
m
(added example)
Line 15: Line 15:
 
'''message''': (string) error message if assert fails '''optional'''<br/>
 
'''message''': (string) error message if assert fails '''optional'''<br/>
  
=== Example ===
+
=== Examples ===
 
'''Checks if a texture is valid'''
 
'''Checks if a texture is valid'''
 
<source lang="lua">
 
<source lang="lua">
Line 27: Line 27:
 
if isValidTexture() then bmp = Bitmap.new(Texture.new(texturepath)) end
 
if isValidTexture() then bmp = Bitmap.new(Texture.new(texturepath)) end
 
end
 
end
 +
</source>
 +
 +
'''Checks if is of type ''number'''''
 +
<source lang="lua">
 +
local value = 12 --> 12
 +
--local value = "hello" --> *** Friction must be a number ***
 +
assert(type(value) == 'number', "*** Friction must be a number ***")
 
</source>
 
</source>
  

Revision as of 01:46, 24 September 2022

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

Examples

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

Checks if is of type number

local value = 12 --> 12
--local value = "hello" --> *** Friction must be a number ***
assert(type(value) == 'number', "*** Friction must be a number ***")

See also

Pcall