Develop

README.md

@@ -47,6 +47,7 @@ A modern, high-performance programming language designed for scientific computin
 - **String functions**: `len`, `concat`, `substring`, `contains`, `starts_with`, `ends_with`, `trim`, `to_int`, `to_float`, `to_string`
 - **List/Array functions**: `len` (indexing and literals supported)
 - **I/O functions**: `print`
+- **PML (Pain Markup Language)**: `pml_load_file`, `pml_parse` - Load and parse PML configuration files
 
 ## Installation
 
@@ -117,6 +118,28 @@ fn main():
     print(sum)
 ```
 
+### PML (Pain Markup Language) Example
+
+PML is a minimalistic declarative data format for configurations and UI structures:
+
+**config.pml:**
+```pml
+app:
+	name: "My App"
+	version: "1.0.0"
+	debug: false
+```
+
+**main.pain:**
+```pain
+fn main():
+    let config = pml_load_file("config.pml")
+    let app_name = config.app.name
+    print("Starting " + app_name)
+```
+
+See [`docs/PML_SPEC.md`](docs/PML_SPEC.md) for complete PML documentation.
+
 ## Project Structure
 
 This is a workspace containing multiple crates:
@@ -132,6 +155,8 @@ This is a workspace containing multiple crates:
   - [`docs/quickstart.md`](docs/quickstart.md) – installation, running programs, `painpkg`.
   - [`docs/stdlib.md`](docs/stdlib.md) – summary of built-in APIs.
   - [`docs/examples.md`](docs/examples.md) – ready-to-run snippets.
+  - [`docs/PML_SPEC.md`](docs/PML_SPEC.md) – PML (Pain Markup Language) specification.
+  - [`docs/examples_pml.md`](docs/examples_pml.md) – PML usage examples.
   - [`docs/JIT_SETUP.md`](docs/JIT_SETUP.md) – JIT compilation setup guide.
 - Generate fresh API docs from source:
 

docs/quickstart.md

@@ -133,9 +133,43 @@ cargo test -p pain-compiler --test integration_test
 cargo bench
 ```
 
-## 9. Next Steps
+## 9. Working with PML (Pain Markup Language)
+
+PML is a minimalistic declarative data format for configurations and UI structures. Create a PML file:
+
+**config.pml:**
+```pml
+app:
+	name: "My App"
+	version: "1.0.0"
+	debug: false
+```
+
+Load and use it in Pain:
+
+```pain
+fn main():
+    let config = pml_load_file("config.pml")
+    let app_name = config.app.name
+    let version = config.app.version
+    print("Starting " + app_name + " v" + version)
+```
+
+Or parse PML from a string:
+
+```pain
+fn main():
+    let pml_source = "title: \"Hello\"\nwidth: 400"
+    let doc = pml_parse(pml_source)
+    print("Parsed PML successfully!")
+```
+
+See [`PML_SPEC.md`](PML_SPEC.md) for complete PML syntax and [`examples_pml.md`](examples_pml.md) for more examples.
+
+## 10. Next Steps
 
 - Explore API details in [`stdlib.md`](stdlib.md).
 - Copy ready-to-run snippets from [`examples.md`](examples.md).
+- Learn about PML in [`PML_SPEC.md`](PML_SPEC.md) and [`examples_pml.md`](examples_pml.md).
 - Use the LSP server (`pain-lsp`) inside VS Code for hover docs, completion, and diagnostics.
 

docs/stdlib.md

@@ -106,6 +106,40 @@ See [`examples.md`](examples.md) for complete class examples.
 | --- | --- | --- |
 | `print` | `fn print(value: dynamic) -> dynamic` | Sends textual representation to stdout |
 
+## PML (Pain Markup Language)
+
+PML is a minimalistic declarative data format for configurations, UI structures, and tree data. PML files use tab-based indentation and support SCALAR, MAP, and LIST node types.
+
+| Function | Signature | Description |
+| --- | --- | --- |
+| `pml_load_file` | `fn pml_load_file(path: str) -> dynamic` | Loads and parses a PML file, returns parsed tree as dynamic object |
+| `pml_parse` | `fn pml_parse(source: str) -> dynamic` | Parses PML string, returns parsed tree as dynamic object |
+
+**Example:**
+```pain
+fn main():
+    # Load PML file
+    let config = pml_load_file("config.pml")
+    let app_name = config.app.name
+    let port = config.app.port
+
+    # Parse PML string
+    let pml_source = "title: \"Hello\"\nwidth: 400"
+    let doc = pml_parse(pml_source)
+    let title = doc.title
+```
+
+**PML File Example (config.pml):**
+```pml
+app:
+	name: "My Application"
+	version: "1.0.0"
+	debug: false
+	port: 8080
+```
+
+See [`PML_SPEC.md`](PML_SPEC.md) for complete PML syntax specification and [`examples_pml.md`](examples_pml.md) for more usage examples.
+
 ## Extending the Stdlib
 
 1. Modify `pain-compiler/src/stdlib.rs`.