Sticky modules¶
Configuration¶
- No specific configuration
Specification¶
Once loaded a sticky module cannot be unloaded unless forced or reloaded.
If module is super-sticky instead of sticky, it cannot be unloaded even if forced, only if it is reloaded afterward
Stickiness definition relies on Module tags
module-tag sticky foo/1.0
defines module foo/1.0 as stickymodule-tag super-sticky foo/1.0
defines module foo/1.0 as super-sticky
Stickiness specified over a symbolic version or a module alias has no effect
module-tag
allows to specify a symbolic module version or a module alias- but associated tag will apply to the symbolic version or alias only
- as modulefile targeted by symbol or alias does not inherit their tags
- so a sticky or super-sticky tag set on a symbolic version or alias has no effect
Sticky module can be swapped with another version from same module when stickiness is defined over module parent name
For instance if stickiness is defined over module foo, foo/1.0 can be swapped with foo/2.0
Such swap could occur from a
restore
or aswitch
sub-commandAs soon as stickiness is defined over a precise module version name (like foo/1.0) such module cannot be swapped by another version of foo module
Stickiness defined over module parent name (like foo) means any version from module foo must be loaded
When stickiness is defined for several module versions using advanced version specifiers like foo@1: or foo@1.0,2.0
- it means stickiness applies to the module versions
- thus they cannot be swapped by another version
In case stickiness is defined over module parent name and another
module-tag
defines stickiness over specific module version name- it means stickiness applies to the module version
- thus these versions targeted specifically with
module-tag
cannot be swapped by another version from same module
When a super-sticky module depends on a non-super-sticky module
- If a forced
purge
command occurs, the dependent module will be unloaded - Which let the super-sticky module with a missing dependency
- If a forced
An error is reported when trying to unload a sticky or super-sticky module
As the expected unload is not performed
So with the return code and message, user knows that what he/she asked for was not done
Same goes for the
purge
command: user expects no more module loaded- so an error is returned as after the command the sticky module is still loaded
When the unload is forced a warning message is reported
- the sticky module is unloaded as expected but a warning message is done
- as the module was tagged not to be unloaded by default
- user should know he/she has done something specific
Current limitations¶
When swapping a sticky module explicitly targeted by the
module-tag
command and which is the default version- For instance
module-tag sticky foo/1.0
andmodule-version foo/1.0 default
- If specified swapped-on module is the generic module name, for instance foo
switch
sub-command raises an error even if the sticky module is the default version (either implicit or explicitly set) for this module
- For instance