Initial commit.

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,31 @@
+---
+name: Bug report
+about: Create a report to help us improve this library.
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+Steps to reproduce the behavior:
+1. Go to '...'
+2. Click on '....'
+3. Scroll down to '....'
+4. See error
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Screenshots**
+If applicable, add screenshots to help explain your problem.
+
+**Environment**
+ - OS, including version
+ - Version of this library
+
+**Additional information**
+Add any other information about the problem here.

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,20 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+**Describe the solution you'd like**
+A clear and concise description of what you want to happen.
+
+**Describe alternatives you've considered**
+A clear and concise description of any alternative solutions or features you've considered.
+
+**Additional context**
+Add any other context or screenshots about the feature request here.

.github/workflows/dart.yml

@@ -0,0 +1,36 @@
+
+name: Dart
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  test:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+        sdk: ['stable', 'dev']
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Dart
+      uses: dart-lang/setup-dart@v1
+      with:
+        sdk: ${{matrix.sdk}}
+    - name: Run tests on Windows after setting the HOME environment variable
+      if: ${{ matrix.os == 'windows-latest' }}
+      run: |
+        $env:HOME = $env:USERPROFILE
+        echo "Env: HOME = $env:HOME"
+        dart pub get
+        dart test
+    - name: Run tests on POSIX
+      if: ${{ matrix.os != 'windows-latest' }}
+      run: |
+        dart pub get
+        dart test --verbose-trace

.gitignore

@@ -0,0 +1,10 @@
+# Files and directories created by pub.
+.dart_tool/
+.packages
+
+# Conventional directory for build output.
+build/
+
+# Omit committing pubspec.lock for library packages; see
+# https://dart.dev/guides/libraries/private-files#pubspeclock.
+pubspec.lock

CHANGELOG.md

@@ -0,0 +1,8 @@
+# Change Log
+
+All notable changes for the new implementation should be documented in this file.
+
+## 0.1.0 - 2021-11-16
+### Added
+- [`TBD`](https://github.com/vsajip/dart-cfg-lib/commit/TBD)
+  Release new implementation.

LICENSE

@@ -0,0 +1,29 @@
+BSD 3-Clause License
+
+Copyright (c) 2021, Vinay Sajip.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its
+   contributors may be used to endorse or promote products derived from
+   this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

README.md

@@ -0,0 +1,121 @@
+# CFG.Config
+
+A Dart library for working with the CFG configuration format.
+
+## Installation
+
+The package can be installed by adding `cfg_lib` to your list of dependencies in `pubspec.yaml`:
+
+```yaml
+cfg_lib: ^0.1.0
+```
+
+## Usage
+
+The CFG configuration format is a text format for configuration files which is similar to, and a superset of, the JSON format. It dates from before its first announcement in [2008](https://wiki.python.org/moin/HierConfig) and has the following aims:
+
+* Allow a hierarchical configuration scheme with support for key-value mappings and lists.
+* Support cross-references between one part of the configuration and another.
+* Provide a string interpolation facility to easily build up configuration values from other configuration values.
+* Provide the ability to compose configurations (using include and merge facilities).
+* Provide the ability to access real application objects safely, where supported by the platform.
+* Be completely declarative.
+
+It overcomes a number of drawbacks of JSON when used as a configuration format:
+
+* JSON is more verbose than necessary.
+* JSON doesn’t allow comments.
+* JSON doesn’t provide first-class support for dates and multi-line strings.
+* JSON doesn’t allow trailing commas in lists and mappings.
+* JSON doesn’t provide easy cross-referencing, interpolation, or composition.
+
+A simple example
+================
+
+With the following configuration file, `test0.cfg`:
+```text
+a: 'Hello, '
+b: 'world!'
+c: {
+  d: 'e'
+}
+'f.g': 'h'
+christmas_morning: `2019-12-25 08:39:49`
+home: `$HOME`
+foo: `$FOO|bar`
+```
+
+You can load and query the above configuration using [iex](https://hexdocs.pm/iex/IEx.html):
+
+Loading a configuration
+-----------------------
+
+The configuration above can be loaded as shown below. In the REPL shell:
+```text
+iex(1)> alias CFG.Config
+CFG.Config
+iex(2)> {:ok, cfg} = Config.from_file("test0.cfg")
+{:ok, #PID<0.218.0>}
+```
+
+The successful call returns a `Config` which can be used to query the configuration.
+
+Access elements with keys
+-------------------------
+Accessing elements of the configuration with a simple key is not much harder than using a map:
+```text
+iex(3)> Config.get(cfg, "a")
+{:ok, "Hello, "}
+iex(4)> Config.get(cfg, "b")
+{:ok, "world!"}
+```
+
+Access elements with paths
+--------------------------
+As well as simple keys, elements can also be accessed using path strings:
+```text
+iex(5)> Config.get(cfg, "c.d")
+{:ok, "e"}
+```
+Here, the desired value is obtained in a single step, by (under the hood) walking the path `c.d` – first getting the mapping at key `c`, and then the value at `d` in the resulting mapping.
+
+Note that you can have simple keys which look like paths:
+```text
+iex(6)> Config.get(cfg, "f.g")
+{:ok, "h"}
+```
+If a key is given that exists in the configuration, it is used as such, and if it is not present in the configuration, an attempt is made to interpret it as a path. Thus, `f.g` is present and accessed via key, whereas `c.d` is not an existing key, so is interpreted as a path.
+
+Access to date/time objects
+---------------------------
+You can also get native Elixir date/time objects from a configuration, by using an ISO date/time pattern in a backtick-string:
+```text
+iex(7)> Config.get(cfg, "christmas_morning")
+{:ok, ~U[2019-12-25 08:39:49.000000Z]}
+```
+Access to other Elixir/Erlang objects
+---------------------------------------
+Access to other Elixir/Erlang objects is also possible using the backtick-string syntax, provided that they are one of:
+* Environment variables
+* Public functions in public modules which take no arguments
+```text
+iex(8)> {:ok, dt} = Config.get(cfg, "now")
+{:ok, ~U[2021-10-16 12:37:37.781391Z]}
+iex(9)> DateTime.diff(DateTime.utc_now, dt)
+6
+ ```
+
+Access to environment variables
+-------------------------------
+To access an environment variable, use a backtick-string of the form `$VARNAME`:
+```text
+iex(10)> elem(Config.get(cfg, "home"), 1) == System.get_env("HOME")
+true
+```
+You can specify a default value to be used if an environment variable isn’t present using the `$VARNAME|default-value` form. Whatever string follows the pipe character (including the empty string) is returned if the VARNAME is not a variable in the environment.
+```text
+iex(11)> Config.get(cfg, "foo")
+{:ok, "bar"}
+```
+
+For more information, see [the CFG documentation](https://docs.red-dove.com/cfg/index.html).

analysis_options.yaml

@@ -0,0 +1,30 @@
+# This file configures the static analysis results for your project (errors,
+# warnings, and lints).
+#
+# This enables the 'recommended' set of lints from `package:lints`.
+# This set helps identify many issues that may lead to problems when running
+# or consuming Dart code, and enforces writing Dart using a single, idiomatic
+# style and format.
+#
+# If you want a smaller set of lints you can change this to specify
+# 'package:lints/core.yaml'. These are just the most critical lints
+# (the recommended set includes the core lints).
+# The core lints are also what is used by pub.dev for scoring packages.
+
+include: package:lints/recommended.yaml
+
+# Uncomment the following section to specify additional rules.
+
+# linter:
+#   rules:
+#     - camel_case_types
+
+# analyzer:
+#   exclude:
+#     - path/to/excluded/files/**
+
+# For more information about the core and recommended set of lints, see
+# https://dart.dev/go/core-lints
+
+# For additional information about configuring this file, see
+# https://dart.dev/guides/language/analysis-options