Artifically limiting the number of reported warnings to 100. Also added benchmarks with random Ints to investigate perf issues when dealing with warnings (future task).
Ideally we would have a custom set-like collection that allows us internally to specify a maximal number of elements. But `EnsoHashMap` (and potentially `EnsoSet`) are still WIP when it comes to being PE-friendly.
The change also allows for checking if the limit for the number of reported warnings has been reached. It will visualize by adding an additional "Warnings limit reached." to the visualization.
The limit is configurable via `--warnings-limit` parameter to `run`.
Closes#6283.
Remove the magical code generation of `enso_project` method from codegen phase and reimplement it as a proper builtin method.
The old behavior of `enso_project` was special, and violated the language semantics (regarding the `self` argument):
- It was implicitly declared in every module, so it could be called without a self argument.
- It can be called with explicit module as self argument, e.g. `Base.enso_project`, or `Visualizations.enso_project`.
Let's avoid implicit methods on modules and let's be explicit. Let's reimplement the `enso_project` as a builtin method. To comply with the language semantics, we will have to change the signature a bit:
- `enso_project` is a static method in the `Standard.Base.Meta.Enso_Project` module.
- It takes an optional `project` argument (instead of taking it as an explicit self argument).
Having the `enso_project` defined as a (shadowed) builtin method, we will automatically have suggestions created for it.
# Important Notes
- Truffle nodes are no longer generated in codegen phase for the `enso_project` method. It is a standard builtin now.
- The minimal import to use `enso_project` is now `from Standard.Base.Meta.Enso_Project import enso_project`.
- Tested implicitly by `org.enso.compiler.ExecCompilerTest#testInvalidEnsoProjectRef`.
related #6323
Fixes the following scenario:
- preprocessor function catches `ThreadInterruptedException` and returns it as a JSON
```json
{"error":"org.enso.interpreter.runtime.control.ThreadInterruptedException"}
```
- engine thinks that the visualization was computed successfully and just returns it to the user (without doing any fallback logic like retrying the computation)
- IDE displays blank visualization
- Missing tests from number parsing.
- Fix type signature on some warning methods.
- Fix warnings on `Standard.Database.Data.Table.parse_values`.
- Added test for `Nothing` and empty string on `use_first_row_as_names`.
- New API for `Number.format` taking a simple format string and `Locale`.
- Add ellipsis to truncated `Text.to_display_text`.
- Adjusted built-in `to_display_text` for numbers to not include type (but also to display BigInteger as value).
- Remove `Noise.Generator` interface type.
- Json: Added `to_display_text` to `JS_Object`.
- Time: Added `to_display_text` for `Date`, `Time_Of_Day`, `Date_Time`, `Duration` and `Period`.
- Text: Added `to_display_text` to `Locale`, `Case_Sensitivity`, `Encoding`, `Text_Sub_Range`, `Span`, `Utf_16_Span`.
- System: Added `to_display_text` to `File`, `File_Permissions`, `Process_Result` and `Exit_Code`.
- Network: Added `to_display_text` to `URI`, `HTTP_Status_Code` and `Header`.
- Added `to_display_text` to `Maybe`, `Regression`, `Pair`, `Range`, `Filter_Condition`.
- Added support for `to_js_object` and `to_display_text` to `Random_Number_Generator`.
- Verified all error types have `to_display_text`.
- Removed `BigInt`, `Date`, `Date_Time` and `Time_Of_Day` JS based rendering as using `to_display_text` now.
- Added support for rendering nested structures in the table viz.
This is the first part of the #5158 umbrella task. It closes#5158, follow-up tasks are listed as a comment in the issue.
- Updates all prototype methods dealing with `Value_Type` with a proper implementation.
- Adds a more precise mapping from in-memory storage to `Value_Type`.
- Adds a dialect-dependent mapping between `SQL_Type` and `Value_Type`.
- Removes obsolete methods and constants on `SQL_Type` that were not portable.
- Ensures that in the Database backend, operation results are computed based on what the Database is meaning to return (by asking the Database about expected types of each operation).
- But also ensures that the result types are sane.
- While SQLite does not officially support a BOOLEAN affinity, we add a set of type overrides to our operations to ensure that Boolean operations will return Boolean values and will not be changed to integers as SQLite would suggest.
- Some methods in SQLite fallback to a NUMERIC affinity unnecessarily, so stuff like `max(text, text)` will keep the `text` type instead of falling back to numeric as SQLite would suggest.
- Adds ability to use custom fetch / builder logic for various types, so that we can support vendor specific types (for example, Postgres dates).
# Important Notes
- There are some TODOs left in the code. I'm still aligning follow-up tasks - once done I will try to add references to relevant tasks in them.
- Fixes InvokeCallableNode to support warnings.
- Strips warnings from annotations in `get_widget_json`.
- Remove `get_full_annotations_json`.
- Fix warnings on Dialect.
Exporting types named the same as the module where they are defined in `Main` modules of library components may lead to accidental name conflicts. This became apparent when trying to access `Problem_Behavior` module via a fully qualified name and the compiler rejected it. This is due to the fact that `Main` module exported `Error` type defined in `Standard.Base.Error` module, thus making it impossible to access any other submodules of `Standard.Base.Error` via a fully qualified name.
This change adds a warning to FullyQualifiedNames pass that detects any such future problems.
While only `Error` module was affected, it was widely used in the stdlib, hence the number of changes.
Closes#5902.
# Important Notes
I left out the potential conflict in micro-distribution, thus ensuring we actually detect and report the warning.
Closes#5151 and adds some additional tests for `cross_tab` that verify duplicated and invalid names.
I decided that for empty or `Nothing` names, instead of replacing them with `Column` and implicitly losing connection with the value that was in the column, we should just error on such values.
To make handling of these easier, `fill_empty` was added allowing to easily replace the empty values with something else.
Also, `{is,fill}_missing` was renamed to `{is,fill}_nothing` to align with `Filter_Condition.Is_Nothing`.
- Fix issue with Geo Map viz.
- Handle invalid format strings better in `Data_Formatter`.
- New constants for the ISO format strings (and a special ENSO_ZONED_DATE_TIME)
- Consistent Date Time format for parsing in all places.
- Avoid throwing exception in datetime parsing.
- Support for milliseconds (well nanoseconds) in Date_Time and Time_Of_Day.
- `Column.map` stays within Enso.
- Allow `Aggregate_Column.Group_By` in `cross_tab` group_by parameter.
- Updated `Widget.Vector_Editor` ready for use by IDE team.
- Added `get` to `Row` to make API more aligned.
- Added `first_column`, `second_column` and `last_column` to `Table` APIs.
- Adjusted `Column_Selector` and associated methods to have simpler API.
- Removed `Column` from `Aggregate_Column` constructors.
- Added new `Excel_Workbook` type and added to `Excel_Section`.
- Added new `SQLiteFormatSPI` and `SQLite_Format`.
- Added new `IamgeFormatSPI` and `Image_Format`.
Closes#5038
- Use the proper widget structure.
- Provide new method `get_widget_json` with whole structure, but keep `get_full_annotations_json` in old form.
- Start to get to some reusable functions.
- Added widget to JS_Object field selections.
When the function is visualized with the `default_preprocessor` method, it returns a dataflow error that shows up in the logs as
```
Cannot encode class org.enso.interpreter.runtime.error.DataflowError to byte array.
```
PR handles dataflow errors in the preprocessor and fallbacks the `to_display_text` value. As a bonus, we get a function visualization.
Implements [#183453466](https://www.pivotaltracker.com/story/show/183453466).
https://user-images.githubusercontent.com/1428930/203870063-dd9c3941-ce79-4ce9-a772-a2014e900b20.mp4
# Important Notes
* the best laziness is used for `Text` type, which makes use of its internal representation to send data
* any type will first compute its default string representation and then send the content of that lazy to the IDE
* special handling of files and their content will be implemented in the future
* size of the displayed text can be updated dynamically based on best effort information: if the backend does not yet know the full width/height of the text, it can update the IDE at any time and this will be handled gracefully by updating the scrollbar position and sizes.
Use `InteropLibrary.isString` and `asString` to convert any string value to `byte[]`
# Important Notes
Also contains a support for `Metadata.assertInCode` to help locating the right place in the code snippets.
**Vector**
- Adjusted `Vector.sort` to be `Vector.sort order on by`.
- Adjusted other sort to use `order` for direction argument.
- Added `insert`, `remove`, `index_of` and `last_index_of` to `Vector`.
- Added `start` and `if_missing` arguments to `find` on `Vector`, and adjusted default is `Not_Found` error.
- Added type checking to `+` on `Vector`.
- Altered `first`, `second` and `last` to error with `Index_Out_Of_Bounds` on `Vector`.
- Removed `sum`, `exists`, `head`, `init`, `tail`, `rest`, `append`, `prepend` from `Vector`.
**Pair**
- Added `last`, `any`, `all`, `contains`, `find`, `index_of`, `last_index_of`, `reverse`, `each`, `fold` and `reduce` to `Pair`.
- Added `get` to `Pair`.
**Range**
- Added `first`, `second`, `index_of`, `last_index_of`, `reverse` and `reduce` to `Range`.
- Added `at` and `get` to `Range`.
- Added `start` and `if_missing` arguments to `find` on `Range`.
- Simplified `last` and `length` of `Range`.
- Removed `exists` from `Range`.
**List**
- Added `second`, `find`, `index_of`, `last_index_of`, `reverse` and `reduce` to `Range`.
- Added `at` and `get` to `List`.
- Removed `exists` from `List`.
- Made `all` short-circuit if any fail on `List`.
- Altered `is_empty` to not compute the length of `List`.
- Altered `first`, `tail`, `head`, `init` and `last` to error with `Index_Out_Of_Bounds` on `List`.
**Others**
- Added `first`, `second`, `last`, `get` to `Text`.
- Added wrapper methods to the Random_Number_Generator so you can get random values more easily.
- Adjusted `Aggregate_Column` to operate on the first column by default.
- Added `contains_key` to `Map`.
- Added ALIAS to `row_count` and `order_by`.
Compiler performed name resolution of literals in type signatures but would silently fail to report any problems.
This meant that wrong names or forgotten imports would sneak in to stdlib.
This change introduces 2 main changes:
1) failed name resolutions are appended in `TypeNames` pass
2) `GatherDiagnostics` pass also collects and reports failures from type
signatures IR
Updated stdlib so that it passes given the correct gatekeepers in place.
Implements https://www.pivotaltracker.com/story/show/184032869
# Important Notes
- Currently we get failures in Full joins on Postgres which show a more serious problem - amending equality to ensure that `[NULL = NULL] == True` breaks hash/merge based indexing - so such joins will be extremely inefficient. All our joins currently rely on this notion of equality which will mean all of our DB joins will be extremely inefficient.
- We need to find a solution that will support nulls and still work OK with indices (but after exploring a few approaches: `COALESCE(a = b, a IS NULL AND b is NULL)`, `a IS NOT DISTINCT FROM b`, `(a = b) OR (a IS NULL AND b is NULL)`; all of which did not work (they all result in `ERROR: FULL JOIN is only supported with merge-joinable or hash-joinable join conditions`) I'm less certain that it is possible. Alternatively, we may need to change the NULL semantics to align it with SQL - this seems like likely the simpler solution, allowing us to generate simple, reliable SQL - the NULL=NULL solution will be cornering us into nasty workarounds very dependent on the particular backend.
Use JavaScript to parse and serialise to JSON. Parses to native Enso object.
- `.to_json` now returns a `Text` of the JSON.
- Json methods now `parse`, `stringify` and `from_pairs`.
- New `JSON_Object` representing a JavaScript Object.
- `.to_js_object` allows for types to custom serialize. Returning a `JS_Object`.
- Default JSON format for Atom now has a `type` and `constructor` property (or method to call for as needed to deserialise).
- Removed `.into` support for now.
- Added JSON File Format and SPI to allow `Data.read` to work.
- Added `Data.fetch` API for easy Web download.
- Default visualization for JS Object trunctes, and made Vector default truncate children too.
Fixes defect where types with no constructor crashed on `to_json` (e.g. `Matching_Mode.Last.to_json`.
Adjusted default visualisation for Vector, so it doesn't serialise an array of arrays forever.
Likewise, JS_Object default visualisation is truncated to a small subset.
New convention:
- `.get` returns `Nothing` if a key or index is not present. Takes an `other` argument allowing control of default.
- `.at` error if key or index is not present.
- `Nothing` gains a `get` method allowing for easy propagation.
- Moved `to_default_visualization_data` to `Standard.Visualization`.
- Remove the use of `is_a` in favour of case statements.
- Stop exporting Standard.Base.Error.Common.
- Separate errors to own files.
- Change constructors to be called `Error`.
- Rename `Caught_Panic.Caught_Panic_Data` -> `Caught_Panic.Panic`.
- Rename `Project_Description.Project_Description_Data` ->`Project_Description.Value`
- Rename `Regex_Matcher.Regex_Matcher_Data` -> `Regex_Matcher.Value` (can't come up with anything better!).
- Rename `Range.Value` -> `Range.Between`.
- Rename `Interval.Value` -> `Interval.Between`.
- Rename `Column.Column_Data` -> `Column.Value`.
- Rename `Table.Table_Data` -> `Table.Value`.
- Align all the Error types in Table.
- Removed GEO Json bits from Table.
- `Json.to_table` doesn't have the GEO bits anymore.
- Added `Json.geo_json_to_table` to add the functions back in.
# Important Notes
No more exports from anywhere but Main!
No more `_Data` constructors!
- Moved `Any`, `Error` and `Panic` to `Standard.Base`.
- Separated `Json` and `Range` extensions into own modules.
- Tidied `Case`, `Case_Sensitivity`, `Encoding`, `Matching`, `Regex_Matcher`, `Span`, `Text_Matcher`, `Text_Ordering` and `Text_Sub_Range` in `Standard.Base.Data.Text`.
- Tidied `Standard.Base.Data.Text.Extensions` and stopped it re-exporting anything.
- Tidied `Regex_Mode`. Renamed `Option` to `Regex_Option` and added type to export.
- Tidied up `Regex` space.
- Tidied up `Meta` space.
- Remove `Matching` from export.
- Moved `Standard.Base.Data.Boolean` to `Standard.Base.Boolean`.
# Important Notes
- Moved `to_json` and `to_default_visualization_data` from base types to extension methods.
- Export all for `Problem_Behavior` (allowing for Report_Warning, Report_Error and Ignore to be trivially used).
- Renamed `Range.Range_Data` to `Range.Value` moved to using `up_to` wherever possible.
- Reviewed `Function`, `IO`, `Polyglot`, `Random`, `Runtime`, `System`.
- `File` now published as type. Some static methods moved to `Data` others into type. Removed `read_bytes` static.
- New `Data` module for reading input data in one place (e.g. `Data.read_file`) will add `Data.connect` later.
- Added `Random` module to the exports.
- Move static methods into `Warning` type and exporting the type not the module.
# Important Notes
- Sorted a few imports into order (ordering by direct import in project, then by from import in project then polyglot and finally self imports).
RuntimeStdlibTest now checks that names in type signatures are qualified (aka poor man's typechecker)
Will be merged after the stdlib tidying by James is complete.
- Moved static methods into `Locale` type. Publishing type not module.
- Stop publishing `Nil` and `Cons` from `List`.
- Tidied up `Json` and merged static in to type. Sorted out various type signatures which used a `Constructor`. Now exporting type and extensions.
- Tidied up `Noise` and merge `Generator` into file. Export type not module.
- Moved static method of `Map` into type. Publishing type not module.
# Important Notes
- Move `Text.compare_to` into `Text`.
- Move `Text.to_json` into `Json`.
* Tidy Bound and Interval.
* Fix Interval tests.
* Fix Interval tests.
* Restructure Index_Sub_Range to new Type/Statics.
* Adjust for Vector exported as a type and static methods on it.
* Tidy Maybe.
* Fix issue with Line_Ending_Style.
* Revert Filter_Condition change.
Fix benchmark test issue.
Tidy imports on Index_Sub_Range.
* Revert Filter_Condition change.
Fix benchmark test issue.
Tidy imports on Index_Sub_Range.
* Can't export constructors unless exported from type in module.
* Fix failing tests.
- Moved `Standard.Database.connect` into `Standard.Database.Database.connect`, so can now just `from Standard.Database import ...`.
- Removed all `Dubious constructor export`s.
- Switched to using `project` for internal imports.
- Moved to using `Value` for private constructors and not re-exporting.
- Export types not modules from `Standard.Database`.
- Broke up `IR` into separate files (Context, Expression, From_Spec, Internal_Column, Join_Kind, Query).
- No longer use `IR.` instead via specific types.
- Broke up `SQL` into separate files (SQL_Type and SQL_Statement).
Additionally;
- Standard.Table: Moved `storage_types` into `Storage`.
- Standard.Table: Switched to using `project` for internal imports.
- Standard.Table.Excel: Renamed modules `Range` to `Excel_Range` and `Section` to `Excel_Section`.
- `Standard.Visualisation`: Switched to using `project` for internal imports.
- `Standard.Visualisation`: Moved to using `Value` for private constructors and not re-exporting.
# Important Notes
- Have not cleared up the `Errors` yet.
- Have not switched to type pattern matching.
- Generally export types not modules from the `Standard.Table` import.
- Moved `new`, `from_rows` the `Standard.Table` library into the `Table` type.
- Renames `Standard.Table.Data.Storage.Type` to `Standard.Table.Data.Storage.Storage`
- Removed the internal `from_columns` method.
- Removed `join` and `concat` and merged into instance methods.
- Removed `Table` and `Column` from the `Standard.Database` exports.
- Removed `Standard.Table.Data.Column.Aggregate_Column` as not used any more.
This change brings by-type pattern matching to Enso.
One can pattern match on Enso types as well as on polyglot types.
For example,
```
case x of
_ : Integer -> ...
_ : Text -> ...
_ -> ...
```
as well as Java's types
```
case y of
_ : ArrayList -> ...
_ : List -> ...
_ : AbstractList -> ...
_ -> ..
```
It is no longer possible to match a value with a corresponding type constructor.
For example
```
case Date.now of
Date -> ...
```
will no longer match and one should match on the type (`_ : Date`) instead.
```
case Date of
Date -> ...
```
is fine though, as requested in the ticket.
The change required further changes to `type_of` logic which wasn't dealing well with polyglot values.
Implements https://www.pivotaltracker.com/story/show/183188846
# Important Notes
~I discovered late in the game that nested patterns involving type patterns, such as `Const (f : Foo) tail -> ...` are not possible due to the old parser logic.
I would prefer to add it in a separate PR because this one is already getting quite large.~ This is now supported!
Makes statics static. A type and its instances have different methods defined on them, as it should be. Constructors are now scoped in types, and can be imported/exported.
# Important Notes
The method of fixing stdlib chosen here is to just not. All the conses are exported to make all old code work. All such instances are marked with `TODO Dubious constructor export` so that it can be found and fixed.
Repairing the constructor name following the types work. Some general tiding up as well.
- Remove `Standard.Database.Data.Column.Aggregate_Column_Builder`.
- Remove `Standard.Database.Data.Dialect.Dialect.Dialect_Data`.
- Remove unused imports and update some type definitions.
- Rename `Postgres.Postgres_Data` => `Postgres_Options.Postgres`.
- Rename `Redshift.Redshift_Data` => `Redshift_Options.Redshift`.
- Rename `SQLite.SQLite_Data` => `SQLite_Options.SQLite`.
- Rename `Credentials.Credentials_Data` => `Credentials.Username_And_Password`.
- Rename `Sql` to `SQL` across the board.
- Merge `Standard.Database.Data.Internal` into `Standard.Database.Internal`.
- Move dialects into `Internal` and merge the function in `Helpers` into `Base_Generator`.
Turns that if you import a two-part import we had special code that would a) add Main submodule b) add an explicit rename.
b) is problematic because sometimes we only want to import specific names.
E.g.,
```
from Bar.Foo import Bar, Baz
```
would be translated to
```
from Bar.Foo.Main as Foo import Bar, Baz
```
and it should only be translated to
```
from Bar.Foo.Main import Bar, Baz
```
This change detects this scenario and does not add renames in that case.
Fixes [183276486](https://www.pivotaltracker.com/story/show/183276486).
Changes following Marcin's work. Should be back to very similar public API as before.
- Add an "interface" type: `Standard.Base.System.File_Format.File_Format`.
- All `File_Format` types now have a `can_read` method to decide if they can read a file.
- Move `Standard.Table.IO.File_Format.Text.Text_Data` to `Standard.Base.System.File_Format.Plain_Text_Format.Plain_Text`.
- Move `Standard.Table.IO.File_Format.Bytes` to `Standard.Base.System.File_Format.Bytes`.
- Move `Standard.Table.IO.File_Format.Infer` to `Standard.Base.System.File_Format.Infer`. **(doesn't belong here...)**
- Move `Standard.Table.IO.File_Format.Unsupported_File_Type` to `Standard.Base.Error.Common.Unsupported_File_Type`.
- Add `Infer`, `File_Format`, `Bytes`, `Plain_Text`, `Plain_Text_Format` to `Standard.Base` exports.
- Fold extension methods of `Standard.Base.Meta.Unresolved_Symbol` into type.
- Move `Standard.Table.IO.File_Format.Auto` to `Standard.Table.IO.Auto_Detect.Auto_Detect`.
- Added a `types` Vector of all the built in formats.
- `Auto_Detect` asks each type if they `can_read` a file.
- Broke up and moved `Standard.Table.IO.Excel` into `Standard.Table.Excel`:
- Moved `Standard.Table.IO.File_Format.Excel.Excel_Data` to `Standard.Table.Excel.Excel_Format.Excel_Format.Excel`.
- Renamed `Sheet` to `Worksheet`.
- Internal types `Reader` and `Writer` providing the actual read and write methods.
- Created `Standard.Table.Delimited` with similar structure to `Standard.Table.Excel`:
- Moved `Standard.Table.IO.File_Format.Delimited.Delimited_Data` to `Standard.Table.Delimited.Delimited_Format.Delimited_Format.Delimited`.
- Moved `Standard.Table.IO.Quote_Style` to `Standard.Table.Delimited.Quote_Style`.
- Moved the `Reader` and `Writer` internal types into here. Renamed methods to have unique names.
- Add `Aggregate_Column`, `Auto_Detect`, `Delimited`, `Delimited_Format`, `Excel`, `Excel_Format`, `Sheet_Names`, `Range_Names`, `Worksheet` and `Cell_Range` to `Standard.Table` exports.
`Vector` type is now a builtin type. This requires a bunch of additional builtin methods for its creation:
- Use `Vector.from_array` to convert any array-like structure into a `Vector` [by copy](f628b28f5f)
- Use (already existing) `Vector.from_polyglot_array` to convert any array-like structure into a `Vector` **without** copying
- Use (already existing) `Vector.fill 1 item` to create a singleton `Vector`
Additional, for pattern matching purposes, we had to implement a `VectorBranchNode`. Use following to match on `x` being an instance of `Vector` type:
```
import Standard.Base.Data.Vector
size = case x of
Vector.Vector -> x.length
_ -> 0
```
Finally, `VectorLiterals` pass that transforms `[1,2,3]` to (roughly)
```
a1 = 1
a2 = 2
a3 = 3
Vector (Array (a1,a2, a3))
```
had to be modified to generate
```
a1 = 1
a2 = 2
a3 = 3
Vector.from_array (Array (a1, a2, a3))
```
instead to accomodate to the API changes. As of 025acaa676 all the known CI checks passes. Let's start the review.
# Important Notes
Matching in `case` statement is currently done via `Vector_Data`. Use:
```
case x of
Vector.Vector_Data -> True
```
until a better alternative is found.
Small clean up PR.
- Aligns a few type signatures with their functions.
- Some formatting fixes.
- Remove a few unused types.
- Make error extension functions be standard methods.
This is a step towards the new language spec. The `type` keyword now means something. So we now have
```
type Maybe a
Some (from_some : a)
None
```
as a thing one may write. Also `Some` and `None` are not standalone types now – only `Maybe` is.
This halfway to static methods – we still allow for things like `Number + Number` for backwards compatibility. It will disappear in the next PR.
The concept of a type is now used for method dispatch – with great impact on interpreter code density.
Some APIs in the STDLIB may require re-thinking. I take this is going to be up to the libraries team – some choices are not as good with a semantically different language. I've strived to update stdlib with minimal changes – to make sure it still works as it did.
It is worth mentioning the conflicting constructor name convention I've used: if `Foo` only has one constructor, previously named `Foo`, we now have:
```
type Foo
Foo_Data f1 f2 f3
```
This is now necessary, because we still don't have proper statics. When they arrive, this can be changed (quite easily, with SED) to use them, and figure out the actual convention then.
I have also reworked large parts of the builtins system, because it did not work at all with the new concepts.
It also exposes the type variants in SuggestionBuilder, that was the original tiny PR this was based on.
PS I'm so sorry for the size of this. No idea how this could have been smaller. It's a breaking language change after all.
Implements https://www.pivotaltracker.com/story/show/182879865
# Important Notes
Note that removing `set_at` still does not make our arrays fully immutable - `Array.copy` can still be used to mutate them.
