Mike Gerwitz
b1c0783c75
I'm not fond of this implementation, which is why it's not fully completed. I wanted to commit this for future reference, and take the opportunity to explain why I don't like it. First: this task started as an idea to implement a third variant to AttrValue and friends that indicates that a value is fixed, in the sense of a fixed-point function: escaped or unescaped, its value is the same. This would allow us to skip wasteful escape/unescape operations. In doing so, it became obvious that there's no need to leak this information through the API, and indeed, no part of the system should care. When we read XML, it should be unescaped, and when we write, it should be escaped. The reason that this didn't quite happen to begin with was an optimization: I'll be creating an echo writer in place of the current filesystem-based copy in tamec shortly, and this would allow streaming XIR directly from the reader to the writer without any unescaping or re-escaping. When we unescape, we know the value that it came from, so we could simply store both symbols---they're 32-bit, so it results in a nicely compressed 64-bit value, so it's essentially cost-free, as long as we accept the expense of internment. This is `XirString`. Then, when we want to escape or unescape, we first check to see whether a symbol already exists and, if so, use it. While this works well for echoing streams, it won't work all that well in practice: the unescaped SymbolId will be taken and the XirString discarded, since nothing after XIR should be coupled with it. Then, when we later construct a XIR stream for writting, XirString will no longer be available and our previously known escape is lost, so the writer will have to re-escape. Further, if we look at XirString's generic for the XirStringEscaper---it uses phantom, which hints that maybe it's not in the best place. Indeed, I've already acknowledged that only a reader unescapes and only a writer escapes, and that the rest of the system works with normal (unescaped) values, so only readers and writers should be part of this process. I also already acknowledged that XirString would be lost and only the unescaped SymbolId would be used. So what's the point of XirString, then, if it won't be a useful optimization beyond the temporary echo writer? Instead, we can take the XirStringWriter and implement two caches on that: mapping SymbolId from escaped->unescaped and vice-versa. These can be simple vectors, since SymbolId is a 32-bit value we will not have much wasted space for symbols that never get read or written. We could even optimize for preinterned symbols using markers, though I'll probably not do so, and I'll explain why later. If we do _that_, we get even _better_ optimizations through caching that _will_ apply in the general case (so, not just for echo), and we're able to ditch XirString entirely and simply use a SymbolId. This makes for a much more friendly API that isn't leaking implementation details, though it _does_ put an onus on the caller to pass the encoder to both the reader and the writer, _if_ it wants to take advantage of a cache. But that burden is not significant (and is, again, optional if we don't want it). So, that'll be the next step. |
||
|---|---|---|
| bin | ||
| build-aux | ||
| core | ||
| design/tpl | ||
| doc | ||
| progtest | ||
| rater | ||
| src | ||
| tamer | ||
| test | ||
| tools | ||
| .gitignore | ||
| .gitlab-ci.yml | ||
| .gitmodules | ||
| .rev-xmle | ||
| .rev-xmlo | ||
| COPYING | ||
| COPYING.FDL | ||
| HACKING | ||
| Makefile.am | ||
| README.md | ||
| RELEASES.md | ||
| VERSION.in | ||
| bootstrap | ||
| c1map.xsd | ||
| configure.ac | ||
| package-lock.json | ||
README.md
TAME
TAME is The Algebraic Metalanguage, a programming language and system of tools designed to aid in the development, understanding, and maintenance of systems performing numerous calculations on a complex graph of dependencies, conditions, and a large number of inputs.
This system was developed at Ryan Specialty Group (formerly LoVullo Associates) to handle the complexity of comparative insurance rating systems. It is a domain-specific language (DSL) that itself encourages, through the use of templates, the creation of sub-DSLs. TAME itself is at heart a calculator—processing only numerical input and output—driven by quantifiers as predicates. Calculations and quantifiers are written declaratively without concern for order of execution.
The system has powerful dependency resolution and data flow capabilities.
TAME consists of a macro processor (implementing a metalanguage), numerous compilers for various targets (JavaScript, HTML documentation and debugging environment, LaTeX, and others), linkers, and supporting tools. The input grammar is XML, and the majority of the project (including the macro processor, compilers, and linkers) is written in a combination of XSLT and Rust.
TAMER
Due to performance requirements, this project is currently being reimplemented in Rust. That project can be found in the tamer/ directory.
Documentation
Compiled documentation for the latest release is available via our GitLab mirror, which uses the same build pipeline as we do on our internal GitLab instance. Available formats are:
Getting Started
To get started, make sure Saxon version 9 or later is available and its path
set as SAXON_CP; that the path to hoxsl is set via HOXSL; and then run
the bootstrap script:
$ export SAXON_CP=/path/to/saxon9he.jar
$ export HOXSL=/path/to/hoxsl/root
$ ./boostrap
Running Test Cases
To run the test cases, invoke make check (or its alias, make test).
Testing Core Features
In order to run tests located at core/test/core/**, a supporting environment
is required. (e.g. mega rater). Inside a supporting rater, either check out a
submodule containing the core tests, or temporarily add them into the
submodule.
Build the core test suite summary page using:
$ make rater/core/test/core/suite.html
Visit the summary page in a web browser and click the Calculate Premium button. If all test cases pass, it will yield a value of $1.
Hacking
Information for TAME developers can be found in the file HACKING.
License
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.