diff options
| -rw-r--r-- | notes/cached_vs_shared_files.txt | 64 | ||||
| -rw-r--r-- | notes/gc.txt | 12 | ||||
| -rw-r--r-- | notes/givemes_normal_classes.txt | 82 | ||||
| -rw-r--r-- | notes/package_build.txt | 10 |
4 files changed, 167 insertions, 1 deletions
diff --git a/notes/cached_vs_shared_files.txt b/notes/cached_vs_shared_files.txt new file mode 100644 index 0000000..eb631f8 --- /dev/null +++ b/notes/cached_vs_shared_files.txt @@ -0,0 +1,64 @@ +Runtime library: Cached vs shared files +======================================= + +Cached files: + +* Are about static content. +* Useful for e.g. things in /usr on *nix. + - But also for configuration or web pages, documents, etc. + if the expiration time is low enough. +* Files are considered (and expected to be) immutable. +* May be cached on subsequent opens. +* May be cached by the runtime, if the process is invoked multiple times. +* May or may not have an underlying file descriptor. +* Might not reload from disk within the expiration time. +* Reads can be "merged" across threads. For example, if there are 200 reqs/s, + and the expiration time is 1 second, then there can be a 200x reduction of + reads at the OS level. +* Not guaranteed to be read in any particular order + (e.g. a read "after" a write might actually happen before the write). +* May be pre-fetched arbitrarily by the runtime. + +Buffered files: + +* Are about dynamic content. +* Useful for files that are generated in "one shot" by other processes. +* For ordering, the time the file is opened matters. But after that point + in time, the reads may be buffered (and hence be executed at different + points in time than in the source code). + +Shared files: + +* Are about state. +* Useful for e.g. databases. +* Guaranteed to be read in order. +* No caching. +* No buffering. +* All I/O operations immediately result in a syscall invocation. + +Class names to use +------------------ + +Theme 1: What they are: + + CachedFile + BufferedFile + SharedFile + +Theme 2: What they do: + + CachingReader + BufferingReader + DirectSyscallReader + +Theme 3: When they should be used: + + StaticReader + DynamicReader + DirectReader + +Theme 4: What the are used for: + + ContentFile + GeneratedFile + MutableFile diff --git a/notes/gc.txt b/notes/gc.txt index 059fd33..1ce8bcb 100644 --- a/notes/gc.txt +++ b/notes/gc.txt @@ -145,3 +145,15 @@ With nested objects: But this cannot encode union types where the kind isn't known at time of allocation. + + +When to perform garbage collection +--------------------------------- + +Is it enough with the following? If so, then no separate "GC thread" or +similar would be required. + +* Allocation +* Resource aquisition (e.g. opening files) +* Some form of "minor collection" on sleep/wait/etc? Or perhaps all + calls that block? diff --git a/notes/givemes_normal_classes.txt b/notes/givemes_normal_classes.txt index ab62c5e..3ad42bd 100644 --- a/notes/givemes_normal_classes.txt +++ b/notes/givemes_normal_classes.txt @@ -1,4 +1,4 @@ -Can service stuff (like giveme`s) be merged into normal classes? +Can service stuff (like giveme's) be merged into normal classes? ================================================================ Super-simple solution with default values @@ -40,3 +40,83 @@ More powerful syntaxes # Better than the above? Somewhat intuitive also. int x from param "-x,--x-value" 0 HttpRequest req from default + +Replace constructors with giveme's? +----------------------------------- + +For example: + + # Definition of `SomeType` + giveme + File f + end + + data + long filepos + end + + entry initialize + code + filepos = 0 + end + + + # Usage + entry main + code + File f = new + f.open "test.txt" + SomeType st = new + st.f = f + st.init + end + + # Usage, with implicit(!) creation on first use: + entry main + code + File f + f.open "test.txt" + SomeType st + st.f = f + st.init + end + + +Or even replace both with typestates: + + # Definition of `SomeType` + data + File f + when initialized + long filepos + end + + entry initialize + transition + initialized + code + filepos = 0 + end + + + # Usage + entry main + code + SomeType st + end + +Or, even more general: + + data + after created + File f + after initialized + long filepos + end + + func initialize + transition + created to initialized + code + filepos = 0 + end diff --git a/notes/package_build.txt b/notes/package_build.txt new file mode 100644 index 0000000..6d3e44d --- /dev/null +++ b/notes/package_build.txt @@ -0,0 +1,10 @@ +Package builds +============== + +Packages usually contain more than just source code, e.g. README.md, etc. + +Also, binary packages could contain non-executable files that need to be +built, e.g. documentation, etc. + +It would be nice to support this in SLUL. Perhaps via some external +tool, or perhaps via some subcommand/extension/plugin of the slul command. |