ahk-eval

name

ahk-eval

description

Live AHK v2 REPL backed by the fork's native Eval() BIF. Execute AHK expressions and get immediate results without writing a multi-line script. Use when testing snippets, checking syntax, or evaluating expressions without creating files. TRIGGER when: user says "eval", "try this expression", "what does X return", "test this snippet", "run this AHK code", "check if this works". Examples: "/ahk-eval StrSplit('a,b,c', ',').Length" returns "3"

AHK v2 Live REPL

Evaluate a single AHK v2 expression and return its result. The fork binary ships a native Eval() BIF — prefer it over the old "spin a script, capture stdout" dance.

How to use

The user supplies one AHK expression (or, less commonly, a short multi-line block). You:

1. Decide single-expression vs. multi-statement.
2. Build the minimal harness script for the chosen mode.
3. Run it with the canonical interpreter.
4. Capture stdout / stderr / exit code and return them.

Mode A — single expression (preferred)

Wrap with Print(Eval(...)) and the #EnableEval directive. One round-trip; no temp boilerplate beyond the directive.

#Requires AutoHotkey v2.1-alpha.30
#EnableEval
try
    Print("{}", String(Eval("<USER_EXPRESSION>") ?? "<unset>"))
catch SyntaxError as e
    Print("SyntaxError: {}", e.Message)
catch UnsetError as e
    Print("UnsetError: {}", e.Message)
catch as e
    Print("{}: {}", e.__Class, e.Message)

Substitute <USER_EXPRESSION> literally. Eval reads/writes locals in its caller, but for one-shot REPL evaluation there are no caller locals to worry about.

Mode B — multi-statement block

When the user provides multiple statements (e.g. a loop with side effects), Eval cannot accept the whole thing. Fall back to inlining the block directly:

#Requires AutoHotkey v2.1-alpha.30
<USER_CODE>

Encourage the user to add Print(...) calls themselves — there's no implicit result to surface.

Execution

TEMP_FILE="$CLAUDE_JOB_DIR/ahk_eval_$$.ahk"
WIN_PATH=$(wslpath -w "$TEMP_FILE")

# 5s timeout. /CrashLog gives us a structured fallback if Eval crashes the interpreter.
timeout 5 "$AHK_EXE" \
    /Headless /ErrorStdOut \
    "$WIN_PATH" \
    1>"$CLAUDE_JOB_DIR/ahk_eval_out.txt" \
    2>"$CLAUDE_JOB_DIR/ahk_eval_err.txt"
exit_code=$?

stdout=$(cat "$CLAUDE_JOB_DIR/ahk_eval_out.txt" 2>/dev/null)
stderr=$(cat "$CLAUDE_JOB_DIR/ahk_eval_err.txt" 2>/dev/null)

rm -f "$TEMP_FILE" "$CLAUDE_JOB_DIR/ahk_eval_out.txt" "$CLAUDE_JOB_DIR/ahk_eval_err.txt"

Examples (Mode A)

Input	Output
StrSplit("a,b,c", ",").Length	3
SubStr("hello world", 7)	world
RegExMatch("abc123", "\d+", &m) ? m[0] : "none"	123
Format("{:04d}", 42)	0042
Map("a",1,"b",2).Count	2
[1,2,3].Map(n => n*n).Reduce((a,b) => a+b, 0)	14

Error reporting

The harness already classifies parse vs. unset vs. other errors. Pass the line through verbatim, then add your own one-line interpretation if the fix is obvious (e.g. missing #EnableEval produces Error: Eval is disabled ... — instruct the user, or rerun with /Eval).

Known v1 limitation

The combo IIFE + maybe operator + || inside Eval crashes the runtime preparse path. If the user supplies something like (() => x? || 42)() to /ahk-eval, fall back to Mode B.

Rules

• Always include #EnableEval in the Mode A harness — never assume the CLI flag.
• Always use /Headless and /ErrorStdOut so dialogs don't appear and runtime errors land on stderr.
• Default timeout: 5 seconds. Bump only if the user asks.
• Write temp files under $CLAUDE_JOB_DIR (never /tmp — parallel jobs collide).
• Clean up temp files in every code path.