To make **App Graph Syntax (AGS)** Turing complete and optimized for mobile, we need to move beyond simple data fetching and introduce **State (Memory), Logic (Conditionals), and Iteration (Loops)**, all while keeping the keystroke count minimal.

By replacing `=` with `:`, we align closer to the "key-value" mental model used in many mobile APIs.

Here is the complete syntax specification for **AGS v1.0**.

---

### 1. The Lexical Foundation
The language is composed of five primary tokens. All are located on the first or second layer of a standard mobile keyboard.

| Token | Name | Purpose | Example |
| :--- | :--- | :--- | :--- |
| `.` | **Noun** | Entity, Object, or Data Source | `.user`, `.product`, `.api` |
| `/` | **Verb** | Action, Function, or Logic Gate | `/get`, `/if`, `/set`, `/loop` |
| `:` | **Assign** | Argument mapping or Value assignment | `id:123`, `name:John` |
| `@` | **Variable** | Local state or temporary memory | `@temp`, `@user_id` |
| `_` | **Terminator** | Ends a logic block (If/Loop) | `_` |

---

### 2. Grammar & Structural Rules

#### A. The Basic Chain (Linear Flow)
Data flows from left to right. The output of one noun/verb pair becomes the context for the next.
> `.user /get id:123 .profile /get avatar`
> *(Get user 123 $\rightarrow$ Get that user's profile $\rightarrow$ Get the avatar)*

#### B. State Management (Variables)
To store data for later use without re-fetching, use the `@` symbol.
> `.user /get id:123 /set @current_user`
> *(Fetches user 123 and saves the object into the variable `@current_user`)*

#### C. Logic & Control Flow (The Turing Complete Part)
Since we have no curly braces, we use the **Terminator (`_`)** to close blocks.

**1. Conditionals (`/if`):**
` /if [condition] [action] _ `
> `/if @current_user.role:admin .admin_panel /show _`
> *(If the variable current_user's role is admin, show the admin panel. End block.)*

**2. Iteration (`/loop` or `/each`):**
` /loop [collection] : [item_name] [action] _ `
> `/loop .orders : .item .item /send_email status:shipped _`
> *(For each order in .orders, call it .item, and send a 'shipped' email for that item. End block.)*

---

### 3. Advanced Mobile Optimizations (Edge Cases)

#### A. Implicit Context (The "Ghost" Noun)
To save typing, if a verb follows another verb without a noun, it assumes the **last mentioned noun**.
*   **Verbose:** `.user /get id:1 /update name:Bob`
*   **AGS Optimized:** `.user /get id:1 /update name:Bob`
*   *(The `/update` verb knows it is still acting on `.user`)*

#### B. String Handling
To avoid quotes `""` (which are tedious on mobile), AGS treats all values as **Strings by default**, unless they are:
1.  **Numbers** (e.g., `123`)
2.  **Booleans** (`true`/`false`)
3.  **Variables** (starting with `@`)
*If a string contains a space, only then are quotes required.*

#### C. The "Pipe" to Variable
Instead of a long `/set` command, use a shortcut to capture the result of a chain.
> `.user /get id:123 -> @u`
> *(Shorthand: Fetch user and pipe the result directly into variable `@u`)*

---

### 4. Comparison: Complex Logic
**Task:** *Fetch all premium users; for each, check if their balance is $> 100$; if so, apply a 10% discount code.*

**Standard JSON/JS Logic (Pseudo):**
```javascript
let users = api.get('.users', {filter: 'premium'});
users.forEach(u => {
  if (u.balance > 100) {
    api.post('/discount', {userId: u.id, code: '10OFF'});
  }
});
```

**App Graph Syntax (AGS):**
> `.users /filter type:premium /loop : .u /if .u.balance: >100 .discount /apply id:.u.id code:10OFF _ _`

**Breakdown of the AGS line:**
1.  `.users /filter type:premium` $\rightarrow$ Gets the list.
2.  `/loop : .u` $\rightarrow$ Iterates through the list, naming each item `.u`.
3.  `/if .u.balance: >100` $\rightarrow$ Checks condition.
4.  `.discount /apply id:.u.id code:10OFF` $\rightarrow$ Executes action.
5.  `_` $\rightarrow$ Closes the `/if`.
6.  `_` $\rightarrow$ Closes the `/loop`.

---

### 5. Final Syntax Cheat Sheet for Developers

| Feature | Syntax | Mobile Key Path |
| :--- | :--- | :--- |
| **Fetch** | `.noun /get id:val` | `.` $\rightarrow$ `/` $\rightarrow$ `:` |
| **Update** | `.noun /update key:val` | `.` $\rightarrow$ `/` $\rightarrow$ `:` |
| **Save** | `.noun /verb $\rightarrow$ @var` | `.` $\rightarrow$ `/` $\rightarrow$ `@` |
| **Condition** | `/if var:val [action] _` | `/` $\rightarrow$ `:` $\rightarrow$ `_` |
| **Loop** | `/loop .list : .item [action] _` | `/` $\rightarrow$ `:` $\rightarrow$ `_` |
| **Pipe** | `.noun /verb $\rightarrow$ .noun /verb` | `.` $\rightarrow$ `/` $\rightarrow$ `.` |

### Summary of Mobile Ergonomics:
*   **No `{}` or `[]`:** No need to enter the deep symbols menu.
*   **No `"` (mostly):** Values are treated as literals unless spaces exist.
*   **Linearity:** The developer can "write" the app logic as a single stream of thought.
*   **Turing Complete:** With variables, loops, and conditionals, you can build any business logic (calculators, CRM flows, API orchestrators) entirely on a mobile keyboard.