Jim Lang is a programming language based on JVM with a comprehensive language system, aimed at helping everyone get started in the field of language development.

add snapshots repository

<repositories> <repository> <id>jim</id> <url>https://oss.sonatype.org/content/repositories/snapshots</url> </repository> </repositories>

set dependency

<dependency> <groupId>com.dafei1288</groupId> <artifactId>jimlang</artifactId> <version>1.0-SNAPSHOT</version> </dependency>

 @Test public void T3() throws IOException{String script = """ function two(){return 2 } ; function one(){return 1 } ; var x = one() + two() ; println("this message is from jimlang!!!") println( x ) ; """; System.out.println(script); System.out.println("--------------------"); JimLangShell shell = new JimLangShell(); Object ret = shell.eval(script,null)} 

or use jsr-223

 @Test public void test01() throws ScriptException{String script = """ function two(){return 2 } ; function one(){return 1 } ; var x = one() + two() ; println("this message is from jimlang!!!") println( x ) ; """; System.out.println(script); System.out.println("--------------------"); ScriptEngineManager manager = new ScriptEngineManager(); ScriptEngine engine = manager.getEngineByName("jim"); engine.eval(script)} 

1. Java >= 21
2. Maven >= 3.8 (If you want to compile and install IoTDB from source code).

mvn clean package -DskipTests=true

• Language: supports early return from nested blocks (if/while/for)
• Build: mvn -q -DskipTests package
• Run a script: bin\\jimlang.cmd examples\\fibonacci.jim
• Start REPL: bin\\jimlang.cmd --cli (or -i)
• Eval one-liner: bin\\jimlang.cmd --eval "println(1+2)" (or -e)
• Read from STDIN: echo println(42) | bin\\jimlang.cmd -
• Enable trace: bin\\jimlang.cmd --trace examples\\fibonacci.jim (or set JIM_TRACE=1)

See also:

• doc/QUICKREF.md language snippets, stdlib, CLI
• doc/ROADMAP.md phases, current status, TODO

• examples/fibonacci.jim Fibonacci sequence
• examples/stdlib_phase3.jim stdlib showcase
• Scoping demos:
  • examples/scope_func.jim function-local shadowing
  • examples/scope_if.jim block scope shadowing
  • examples/scope_assign_outer.jim assign to outer var inside function

var o ={a: 1, b: [2,3] } var j = json_encode(o) var x = json_decode(j) println(json_pretty(o, 2)) // file IO json_dump(o, "tmp.json", 2) var ox = json_load("tmp.json") yml_dump(o, "tmp.yml", 2) // var oy = yml_load("tmp.yml") // requires SnakeYAML 

• Triple-quoted multi-line strings: ''' ... ''' (preserves newlines/whitespace). See doc/QUICKREF.md.\n\n## First-class functions

Note: sysfunctions are also first-class values. You can assign and call them:

var p = println p("ok") 

function add(a,b){return a + b } var d = add println( d(2, 3) ) 

• Built-ins: env_get(name[, default]) / env_all() / load_env(path[, override=false])
• Behavior:
  • env_get reads from an in-memory overlay (populated via load_env(..., true)) before System.getenv
  • env_all returns merged overlay + process envs (overlay wins)
  • load_env parses .env (supports leading export, # comments, key=value, strip quotes). If file missing, returns{}. See doc/QUICKREF.md.## Web Server (built-in)

function api(req){return{ok: true } } start_webserver(8080, "/api/ping", "GET", api) 

• Routes: use triples (path, method, handler) or route(path, method, handler) array
• Handler receives req: method, path, params/splat, query, headers, body, json, cookies
• Response helpers: send_text, send_html, send_json, redirect, set_header, response, response_bytes
• Files: send_file, attachment_file; bytes: file_read_bytes

See more: doc/QUICKREF.md (Web section)

• examples/web_app
• examples/env/web_port.jim read .env for PORT and GREETING 锟?complete web app (routes, static, cookies, download)

• Use JimLangShell.eval(script, sourceName, context) to inject variables:
  • The entire map is exposed as ctx (Map).
  • Identifier-friendly keys ([A-Za-z_][A-Za-z0-9_]*) are also injected as globals (e.g., input, discount).
  • Keys with special characters are accessed by bracket syntax: ctx["user-id"] (currently read-only).

Example (Java):

Map<String,Object> input = Map.of( "name", "Alice", "scores", Arrays.asList(2,3,5,7) ); Map<String,Object> ctx = newLinkedHashMap<>(); ctx.put("input", input); ctx.put("discount", 0.85); ctx.put("user-id", "u123"); Stringscript = String.join("\n", "var sum = 0;", "for (var i = 0; i < input.scores.length; i = i + 1){sum = sum + input.scores[i]}", "var uid = ctx[\"user-id\"];", "{name: input.name, final: sum * discount, uid: uid }" ); Objectret = newJimLangShell().eval(script, "<inject-demo>", ctx); System.out.println(ret);

• More examples:
  • examples/DemoEvalInjectCtx.java
  • examples/DemoEvalRoundTrip.java
  • examples/DemoCallFunctionWithParams.java

Note: ctx["锟斤拷"] is read-only for now; write support (e.g. ctx["k"] = v) can be added later.