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Crash when default start rule has parameters

See original GitHub issue

> ohm.grammar('G { Start<x> = x }').match('x')
TypeError: Cannot read property 'getExprType' of undefined
    at Apply.pexprs.Apply._calculateExprType (/Users/dubroy/dev/cdg/ohm/src/pexprs-getExprType.js:112:28)
    at Apply.pexprs.PExpr.getExprType (/Users/dubroy/dev/cdg/ohm/src/pexprs-getExprType.js:33:19)
    at Apply.PExpr.newInputStreamFor (/Users/dubroy/dev/cdg/ohm/src/pexprs.js:39:23)
    at Object.Grammar._match (/Users/dubroy/dev/cdg/ohm/src/Grammar.js:102:38)
    at Object.Grammar.match (/Users/dubroy/dev/cdg/ohm/src/Grammar.js:93:22)
    at repl:1:35
    at REPLServer.defaultEval (repl.js:252:27)
    at bound (domain.js:287:14)
    at REPLServer.runBound [as eval] (domain.js:300:12)
    at REPLServer.<anonymous> (repl.js:417:12)

Issue Analytics

State:
Created 8 years ago
Comments:5 (5 by maintainers)

Top GitHub Comments

1reaction

pdubroycommented, Mar 17, 2016

Not sure how we should handle this. I wonder if we should require that the default start rule for a grammar have no parameters.

0reactions

mroedercommented, Mar 18, 2016

After fixing #76, the error message you will get now is Error: Wrong number of parameters for rule Start (expected 1, got 0). You can run the match by explicitly calling match('x', 'Start<"x">'). Does that fix and close this issue (for now)?