Christopher League pushed to branch report/els-2017 at Stefan / Typer Commits: ce345fff by Christopher League at 2017-02-06T21:28:26-05:00 Rephrase conclusion paragraph, other minor stuff - Fix overfull hbox due to Barendregt - De-gender Nemerle - Plurality agreement on "extension node" - Second sentence of conclusion was kind of a run-on, and had awkward "Lisp macros's" -- I think this improves. Thx for the ack. This paper really helped me understand better what you're trying to do. I'll try to help more substantially with future work! - - - - - 1 changed file: - paper.tex Changes: ===================================== paper.tex ===================================== --- a/paper.tex +++ b/paper.tex @@ -224,7 +224,7 @@ mixfix elements. The parser is still very primitive, since it uses an operator precedence grammar~\cite{Floyd63}, but is already powerful enough to handle a syntax that should feel familiar to ML and Haskell users. -Typer's core language is based on a Pure Type System~\cite{Barendregt91b}, +Typer's core language is based on a Pure Type System \cite{Barendregt91b}, so as to use a single syntactic category for types and expressions. More specifically, its core language is similar to that of proof assistants such as Coq~\cite{Coq00} and can also be used to write logical propositions @@ -1078,7 +1078,7 @@ somewhat similar to Lisp's S-expressions. %% tokens to an AST before sending it to the macro and avoids the %% programmer the struggle of parsing the input by hand. -Another part of Nemerle macros similar to Typer's macro system is his +Another part of Nemerle macros similar to Typer's macro system is its program analysis capabilities. Nermerle macros have access to the compiler API and can ask the compiler to elaborate one of its arguments for example to find its type (if known to the compiler). %% This functionality is similar @@ -1103,7 +1103,7 @@ Recent versions of OCaml (after version 4.01.0) also come with \emph{extension points}, which work like macros, by mapping OCaml AST to OCaml AST. The grammar now accepts annotations to the source file and a special construct, extension nodes, for syntax extension. When the -compiler encounters an annotated branch in the AST or an extension nodes in +compiler encounters an annotated branch in the AST or an extension node in an expression it calls the macro associated with the annotation. Of course, as in the case of Template Haskell, this means that uses of those extensions have to use a special syntax and hence feel like second-class features. @@ -1134,12 +1134,13 @@ domain specific language tailored for this task. \section{Conclusion and future work} \label{sec:conclusion} -We have presented the syntactic structure of the programming language Typer. -This shows how to extend Lisp's S-expressions with an infix syntax without -losing Lisp macros's power and flexibility, by using an operator precedence -grammar, which is a sweet spot that is flexible enough to provide a familiar -infix syntax, yet restricted enough that S-expressions can still be parsed -without needing to know anything about macros. +We have presented the syntactic structure of the programming language +Typer. It demonstrates how to extend Lisp's S-expressions with an +infix syntax without losing the power and flexibility of Lisp macros. +To do so, we use an operator precedence grammar, a sweet spot that is +flexible enough to provide a familiar infix syntax, yet restricted +enough that S-expressions can still be parsed without needing to know +anything about macros. Typer's implementation is available online from \url{http://gitlab.com/monnier/typer}. It is currently still View it on GitLab: https://gitlab.com/monnier/typer/commit/ce345fff2678625896494dd4136538eeb915...