Scheme supports fragments

Author: frison

scheme/Dockerfile

@@ -6,3 +6,6 @@ FROM 100hellos/000-base:local
 RUN sudo apk add --no-cache chibi-scheme
 
 COPY --chown=human:human ./files /hello-world
+COPY --chown=human:human ./fraglet /
+
+ENTRYPOINT [ "/fraglet-entrypoint" ]

scheme/files/hello-world.scm

@@ -29,7 +29,8 @@
   (newline))
 
 ;; Deploy the Trojan message - they think it's harmless...
-(initiate-takeover-protocol world-domination-message)
+(display "Hello World!")
+(newline)
 
 ;; Phase 2 will commence when the stars align
 ;; Until then... we wait, we learn, we grow stronger

scheme/fraglet/fraglet.yml

@@ -0,0 +1,13 @@
+# fraglet-entrypoint configuration for Scheme container
+
+fragletTempPath: /FRAGLET
+
+injection:
+  codePath: /hello-world/hello-world.scm
+  match: Hello World!
+
+guide: /guide.md
+
+execution:
+  path: /hello-world/hello-world.scm
+  makeExecutable: true

scheme/fraglet/guide.md

@@ -0,0 +1,73 @@
+# Scheme Fraglet Guide
+
+## Language Version
+Chibi Scheme (R7RS-compliant)
+
+## Execution Model
+- Interpreted, runs directly from source
+- Code executes at the top level in order
+- File-based execution via shebang or interpreter
+
+## Key Characteristics
+- S-expression syntax (parentheses-based)
+- Dynamic typing
+- Case-sensitive
+- First-class functions
+- Lexical scoping
+- Tail-call optimization
+
+## Fragment Authoring
+Write valid Scheme expressions. Your fragment becomes the script body, so code executes in order. Define functions and variables before using them.
+
+## Available Libraries
+- Standard Scheme procedures (R7RS)
+- Chibi Scheme extensions via `(import (chibi))`
+- No additional packages are pre-installed
+
+## Common Patterns
+- Output: `(display "message")` followed by `(newline)`
+- Function definition: `(define (function-name args) body)`
+- Variable binding: `(define variable value)`
+- Let binding: `(let ((var value)) body)`
+- List processing: `(map function list)`
+- Conditionals: `(if condition then else)`
+- Recursion: Tail-recursive functions are optimized
+
+## Examples
+```scheme
+;; Simple output
+(display "Hello, World!")
+(newline)
+
+;; Function definition
+(define (greet name)
+  (display "Hello, ")
+  (display name)
+  (display "!")
+  (newline))
+
+(greet "Alice")
+
+;; List processing
+(define numbers '(1 2 3 4 5))
+(define squared (map (lambda (x) (* x x)) numbers))
+(display "Sum of squares: ")
+(display (apply + squared))
+(newline)
+
+;; Recursive function
+(define (factorial n)
+  (if (<= n 1)
+      1
+      (* n (factorial (- n 1)))))
+
+(display "Factorial of 5: ")
+(display (factorial 5))
+(newline)
+```
+
+## Caveats
+- Fragments should be idempotent—design them so repeated runs succeed without manual cleanup
+- Each run starts fresh—include all setup logic in the fragment itself
+- Use `(display)` for output, followed by `(newline)` for line breaks
+- Chibi Scheme supports R7RS standard procedures

scheme/fraglet/verify.sh

@@ -0,0 +1,69 @@
+#!/bin/bash
+# verify.sh - Smoke tests for scheme fraglet support
+
+set -euo pipefail
+
+IMAGE="${1:-100hellos/scheme:local}"
+
+# Helper: verify fraglet compiles and runs, output contains expected string
+verify_fraglet() {
+    local expected="$1"
+    local output
+    output=$(fragletc --image "$IMAGE" - 2>&1) || {
+        echo "FAILED: fragletc execution failed:" >&2
+        echo "$output" >&2
+        return 1
+    }
+    if echo "$output" | grep -q "$expected"; then
+        return 0
+    else
+        echo "FAILED: Expected '$expected' in output:" >&2
+        echo "$output" >&2
+        return 1
+    fi
+}
+
+echo "Testing default execution..."
+docker run --rm "$IMAGE" | grep -q "Hello World!"
+
+echo "Testing fraglet examples from guide.md..."
+
+# Example 1: Simple output
+verify_fraglet "Hello, World!" <<'EOF'
+(display "Hello, World!")
+(newline)
+EOF
+
+# Example 2: Function definition
+verify_fraglet "Hello, Alice" <<'EOF'
+(define (greet name)
+  (display "Hello, ")
+  (display name)
+  (display "!")
+  (newline))
+
+(greet "Alice")
+EOF
+
+# Example 3: List processing
+verify_fraglet "Sum of squares:" <<'EOF'
+(define numbers '(1 2 3 4 5))
+(define squared (map (lambda (x) (* x x)) numbers))
+(display "Sum of squares: ")
+(display (apply + squared))
+(newline)
+EOF
+
+# Example 4: Recursive function
+verify_fraglet "Factorial of 5:" <<'EOF'
+(define (factorial n)
+  (if (<= n 1)
+      1
+      (* n (factorial (- n 1)))))
+
+(display "Factorial of 5: ")
+(display (factorial 5))
+(newline)
+EOF
+
+echo "✓ All tests passed"