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| − | == Motivation ==
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| − | This can be used as a centralized place to discuss parts of D2's design that are controversial or suboptimal in retrospect.
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| − | Also discussed here are features that would be worthy of consideration in a hypothetical successor for D2, let's call it D3 (or E!).
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| − | This page came up from email thread http://forum.dlang.org/post/ygmtislwwhfftiqrujan@forum.dlang.org.
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| − |
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| − | Desirable properties:
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| − | * move features & special syntax from language to library whenever possible
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| − | * increase syntax & feature orthogonality (no special case for strings, prefer explicit to implicit)
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| − | * increase DRY-ness of code
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| − | * design grammar to be easy to parse and provide reference compiler as a library
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| − | * feature AST macros to simplify a number of constructs
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| − | * prefer automatic attribute inference over manual annotation
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| − |
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| − | Staying as close as possible to D2's syntax is not necessarily a goal, as automatic translation tools can easily take care of this: clarity of target language is a more important role.
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| − |
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| − | == Features to drop ==
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| − |
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| − | * remove language builtins (sort / reverse / foreach_reverse / complex numbers), see http://dlang.org/deprecate.html
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| − |
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| − | * get rid of opSlice/opSliceAssign etc:
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| − | ** a..b is instead syntax sugar for a Slice object:
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| − | ** rationale for opSlice, opSliceAssign, vs a..b being syntax sugar for a Slice struct? http://forum.dlang.org/post/mailman.551.1365290408.4724.digitalmars-d-learn@puremagic.com
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| − |
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| − | * get rid of C-style expression lists in parenthesis; these would be reserved for tuples
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| − |
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| − | * strings: stop conflating range of code points with range of code units:
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| − | ** "foo" represents a range of code points
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| − | ** "foo".rep represents a range of code units, eg: immutable(char)[]
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| − | ** This would remove a *lot* of special case code in phobos and make it easier to write generic code, eg, would remove need for distinguishing ElementType vs ForeachType
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| − | ** I've discussed this in email:"iteration over a string"
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| − | ** Andrei mentioned it here as well: http://forum.dlang.org/post/l3h49k$b6$1@digitalmars.com
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| − | "It is my opinion that a better solution exists (in the form of making representation accessible only through a property .rep)"
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| − |
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| − | * stop conflating paths with strings; would make a lot of code safer and cross platform; would still allow implicit conversion via alias this.
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| − | ** http://forum.dlang.org/post/op.wx7lqwvx54xghj@puck.auriga.bhead.co.uk + code
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| − |
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| − | * get rid of @property
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| − |
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| − | * get rid of /**/ since we have nesting /++/
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| − |
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| − | * pragma(msg,) shouldn't insert "\n" (easy to add, impossible to remove)
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| − |
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| − | * remove 'version(foo)' in favor of: static if(versions.foo), which would be more orthogonal. versions is an implicitly imported module that contains (for example):
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| − | version.osx=true
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| − | version.posix=true
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| − | version.windows=false
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| − | //plus other versions defined on command line
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| − | => no new syntax
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| − |
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| − | == Safety ==
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| − | * default is @safe/@pure ; attributes are automatically inferred and exported in di interface files
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| − |
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| − | == Separate Compilation ==
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| − |
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| − | * is virtual by default a good idea with separate compilation model?
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| − |
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| − | == Features to add ==
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| − |
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| − | * AST macros
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| − | ** proposal: https://dl.dropboxusercontent.com/u/18386187/ast_macros.html#scroll_to_here
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| − | ** would enable many features; eg:
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| − | *** supersedes: "proposal: a new string litteral to embed variables in a string" http://forum.dlang.org/post/mailman.94.1383254681.9546.digitalmars-d@puremagic.com
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| − | *** supersedes: "feature request: __ARGS__ for logging (cf __FILE__, __LINE__, __FUNC___)" http://forum.dlang.org/post/godmqvdatmjvkyjybkoa@forum.dlang.org
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| − |
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| − | * python style named parameter arguments
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| − |
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| − | * Yield return
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| − |
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| − | * R-value references
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| − |
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| − | * Safe references
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| − |
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| − | * language syntax for tuples; unify syntax for compile time tuples with runtime tuples
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| − | ** could follow DIP32 but use (a,b) syntax instead; we would get rid of C-style expression lists to enable this
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| − |
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| − | === Arrays and Ranges ===
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| − |
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| − | * multidimensional indexing and slicing:
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| − | ** https://github.com/D-Programming-Language/dmd/pull/443
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| − | ** http://homepages.uni-regensburg.de/~nen10015/documents/D-multidimarray.html
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| − |
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| − | * builtin slices with begin..end:step or begin..end..step
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| − |
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| − | == Compilation ==
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| − |
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| − | * proposal: lazy compilation model for compiling binaries: http://forum.dlang.org/post/mailman.1357.1371876331.13711.digitalmars-d@puremagic.com
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| − |
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| − | * allow JIT code, to allow runtime eval statements (for REPL etc).
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| − |
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| − | * Compiler as a library (eg llvm/clang toolchain)
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| − |
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| − | * Compiler written in D2, and then bootstrapped from their as done in rust and many other languages
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| − |
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| − | == Tooling ==
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| − | * Incremental compilation support in rdmd: http://d.puremagic.com/issues/show_bug.cgi?id=9673
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| − | * improved dmd/rdmd command line: http://wiki.dlang.org/DIP41
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| − |
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| − | == Syntax changes ==
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| − | * full UFCS support: foo.mixin, foo.assert, foo.stringof, foo.typeof
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| − |
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| − | * More lightweight syntax:
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| − | ** Go style a := b meaning auto a = b
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| − |
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| − | ** semi-column optional
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| − |
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| − | ** Go style lightweight if/while/etc expressions that don't require () around the if statement:
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| − | <syntaxhighlight lang="d">
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| − | while x>=0 {...}
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| − | </syntaxhighlight>
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| − |
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| − | == Language interop ==
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| − | * Allow transparently including C headers in code as in Go; could use swig behind the scenes
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| − |
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| − | == More controversial features to add ==
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| − | * store code as AST,
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| − | ** The 1st idea is to get rid of styleguides completely and allow people to read/write code with their preferred style. Codes gets stored and exchanged as AST; clients read the AST and converts it on the fly as source code in the user's preferred formatting.
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| − | ** speeds up compilation: only currently modified code needs to get translation from source to AST
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| − | ** More future proof and eases refactoring
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| − | ----
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| − | Page originally created by Timothee Cour on 11/09/2013; copyright: public domain.
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| − | TODO: add discussion/DIP/webpage links to each item
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