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alloc_buffer_markers_on_buffer

January 19th 2020
Allocate buffer markers inside a managed scope and attach them to a buffer

Signature

C++
Managed_Object
alloc_buffer_markers_on_buffer(Application_Links* app,
                               Buffer_ID buffer_id,
                               i32 count,
                               Managed_Scope* optional_extra_scope);

Parameters

app

the standard custom layer context pointer

buffer_id

the buffer on which them markers will be attached

count

the number of markers to allocate

optional_extra_scope

either a null pointer, or a pointer to a managed scope

Return

on success, when the buffer exists, and the optional_extra_scope is valid, a new managed object id, otherwise zero

Details

By default, markers are allocated in the scope of the buffer they are attached to, this is how their lifetime is tied to the lifetime of the buffer. When an additional scope is supplied, it is combined with the buffer's scope via the same joining operation used in get_managed_scope_with_multiple_dependencies and the markers are allocated in that scope instead.
Markers are updated by edits to the buffer to which they are attached, so that they the same position in the buffer even as text is shifted around by edit operations. This can be used, for instance, to track the locations of compilation errors even as some compilation errors have already been fixed and shifted the position of later errors.

Related

get_managed_scope_with_multiple_dependencies
Marker