Imported sources

.gitattributes

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+*.bat           text eol=crlf

.github/workflows/gradle.yml

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+name: Java CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up JDK 17
+        uses: actions/setup-java@v2
+        with:
+          java-version: "17"
+          distribution: "temurin"
+      - name: Validate Gradle wrapper
+        uses: gradle/wrapper-validation-action@e6e38bacfdf1a337459f332974bb2327a31aaf4b
+      - name: Build
+        run: ./gradlew build
+      - name: Test
+        run: ./gradlew test

.gitignore

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+.gradle/
+.idea/
+build/
+bin/
+html/

COPYRIGHT.md

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+Copyright (c) 2022 Maroontress Fast Software. 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.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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

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+# IntExpr
+
+IntExpr is a Java library to evaluate `int` expressions. The expression has
+some similarities in the syntax to the C programming language.
+
+## Examples
+
+[The following code](src/test/java/com/example/EvalDemo.java) evaluates the
+string that represents an integer expression and prints the result:
+
+```java
+package com.example;
+
+import com.maroontress.intexpr.IntExpr;
+
+public final class EvalDemo {
+    public static void main(String[] args) {
+        System.out.println(IntExpr.eval(args[0]));
+    }
+}
+```
+
+The output would be as follows:
+
+```plaintext
+$ java com.example.EvalDemo '(1+2*3<<4)%5'
+2
+```
+
+Internally, the specified expression is converted to the expression in
+[_Reverse Polish notation_][wikipedia-rpn] (RPN) before evaluation. The
+expressions in RPN do not contain parentheses.
+[The following code](src/test/java/com/example/TreeDemo.java) prints the syntax
+tree representing the expression in RPN, which corresponds to the specified
+expression:
+
+```java
+package com.example;
+
+import com.maroontress.intexpr.IntExpr;
+
+public final class TreeDemo {
+    public static void main(String[] args) {
+        System.out.println(IntExpr.toTree(args[0]));
+    }
+}
+```
+
+The output would be as follows:
+
+```plaintext
+$ java com.example.TreeDemo '(1+2*3<<4)%5'
+MOD
+ ├ SHL
+ │  ├ ADD
+ │  │  ├ CONST 1
+ │  │  └ MUL
+ │  │     ├ CONST 2
+ │  │     └ CONST 3
+ │  └ CONST 4
+ └ CONST 5
+```
+
+The opcodes that the tree includes (such as `ADD`, `MUL`, `CONST`, etc.) are
+defined in
+[`enum Opcode`](src/main/java/com/maroontress/intexpr/impl/Opcode.java).
+
+## Numbers
+
+Numbers are 32-bit signed integers in two's-complement notation (like values of
+`int` type in Java and C#, `int32_t` type in C23, and so on). They can
+represent integers from &minus;2147483648 to 2147483647.
+
+## Expressions
+
+A simple expression is just an integer constant.
+
+Note that the minimum integer (&minus;2147483648) cannot be constant because
+the expression `-2147483648` is a unary `-` operator followed by `2147483648`,
+and the integer is greater than the maximum integer (2147483647). So, you have
+to represent the minimum integer with `(-2147483647 - 1)`.
+
+In the following descriptions of legal expressions, _expr_ refers to a complete
+expression:
+
+- `(` _expr_ `)`: The parentheses alter the standard precedence to force the
+  evaluation of the expression to precede the operation outside of them.
+- unary `+` _expr_: The result is the expression itself (that is, no
+  operation).
+- unary `-` _expr_: The result is the negation of the expression.
+- unary `!` _expr_:  The result is 1 if _expr_ is 0, otherwise 0.
+- unary `~` _expr_: The result is the logical negation on each bit, forming the
+  ones' complement of the given binary value.
+- _expr_ `*` _expr_: The result is the product of the two expressions.
+- _expr_ `/` _expr_: The result is the quotient of the two expressions.
+- _expr_ `%` _expr_: The result is the remainder of the two expressions.
+- _expr_ `+` _expr_: The result is the sum of the two expressions.
+- _expr_ `-` _expr_: The result is the difference between the two expressions.
+- _expr1_ `<<` _expr2_: The result is the left arithmetic shift of _expr1_ by
+  _expr2_.
+- _expr_ `>>` _expr_: The result is the right arithmetic shift of _expr1_ by
+  _expr2_.
+- _expr1_ `<` _expr2_: The result is 1 if _expr1_ is strictly less than
+  _expr2_, otherwise 0.
+- _expr1_ `<=` _expr2_: The result is 1 if _expr1_ is less than or equal to
+  _expr2_, otherwise 0.
+- _expr1_ `>` _expr2_: The result is 1 if _expr1_ is strictly greater than
+  _expr2_, otherwise 0.
+- _expr1_ `>=` _expr2_: The result is 1 if _expr1_ is greater than or equal to
+  expr2, otherwise 0.
+- _expr1_ `==` _expr2_: The result is 1 if _expr1_ is equal to _expr2_,
+  otherwise 0.
+- _expr1_ `!=` _expr2_: The result is 1 if _expr1_ is not equal to _expr2_,
+  otherwise 0.
+- _expr_ `&&` _expr_: The result is 1 if both expressions are non-zero,
+  otherwise 0.
+- _expr_ `||` _expr_: The result is 1 if either expression is non-zero,
+  otherwise 0.
+
+The operator precedence is as follows:
+
+| Precedence | Operator                     | Associativity |
+| :---       | :---                         | :---          |
+| highest    | unary `+` `-` `!` `~`        |               |
+|            | `*` `/` `%`                  | Left-to-right |
+|            | `+` `-`                      | Left-to-right |
+|            | `<<` `>>`                    | Left-to-right |
+|            | `<` `<=` `>` `>=`            | Left-to-right |
+|            | `==` `!=`                    | Left-to-right |
+|            | `&`                          | Left-to-right |
+|            | `^`                          | Left-to-right |
+|            | `\|`                         | Left-to-right |
+|            | `&&`                         | Left-to-right |
+| lowest     | `\|\|`                       | Left-to-right |
+
+## Errors
+
+Syntax errors (such as a mismatched or missing parenthesis, a stray token, an
+unknown token) throw an `IllegalArgumentException`. The division by zero and
+the overflow during the evaluation throw an `ArithmeticException`.
+
+## API Reference
+
+- [com.maroontress.intexpr][apiref-maroontress.intexpr] module
+
+[wikipedia-rpn]: https://en.wikipedia.org/wiki/Reverse_Polish_notation
+[apiref-maroontress.intexpr]:
+  https://maroontress.github.io/IntExpr-Java/api/latest/html/index.html

build.gradle

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+plugins {
+    id 'java'
+    id 'jacoco'
+    id 'checkstyle'
+    id 'maven-publish'
+}
+
+group 'com.maroontress'
+version '1.0'
+
+repositories {
+    mavenCentral()
+    maven {
+        url = uri('https://maroontress.github.io/maven')
+    }
+}
+
+dependencies {
+    implementation 'com.maroontress:clione:1.0'
+    testImplementation 'org.hamcrest:hamcrest:2.2'
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.8.2'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.8.2'
+}
+
+compileJava {
+    options.encoding = 'UTF-8'
+    sourceCompatibility = 11
+    targetCompatibility = 11
+}
+
+compileTestJava {
+    options.encoding = 'UTF-8'
+    sourceCompatibility = 14
+}
+
+test {
+    useJUnitPlatform()
+    finalizedBy jacocoTestReport
+}
+
+jacocoTestReport {
+    dependsOn test
+    reports {
+        xml.required = false
+        csv.required = false
+        html.outputLocation = layout.buildDirectory.dir('reports/jacoco-html')
+    }
+}
+
+java {
+    withJavadocJar()
+    withSourcesJar()
+}
+
+javadoc {
+    options.addStringOption('locale', 'en-US')
+    options.encoding = 'UTF-8'
+}
+
+checkstyle {
+    toolVersion '9.2.1'
+}
+
+checkstyleMain {
+    configFile = file("${rootDir}/config/checkstyle/main.xml")
+}
+
+checkstyleTest {
+    configFile = file("${rootDir}/config/checkstyle/test.xml")
+}
+
+publishing {
+    repositories {
+        maven {
+            name = 'LocalFile'
+            url = uri("${localMavenRepo}")
+        }
+    }
+    publications {
+        gpr(MavenPublication) {
+            from(components.java)
+        }
+    }
+}