This simplifies the code a bit and makes the AST more regular (each node
type has a fixed set of properties). The latter may get useful later
when generalizing visitors.
|quote| is used outside of the |parse| function so it must be defined in
more outer scope.
Fixes a problem (introduced in e9d8dc8eba)
where construction of some error messages could throw an error.
This has two main benefits:
1. The knowledge about scoping params in at one designated place,
making all future adjustments in this area easier.
2. Action-related code does not handle sequences specially anymore.
Such knowledge/behavior doesn't belong there.
Before this change, knowledge about variable names was spread between
the |computeStackDepths| pass and the code emitter code. For example,
the fact that the |&...| expression needs one variable to store a
position was represented in both places.
This changes consolidates that knowledge and introduces a new
|computeVarNames| pass. This pass replaces old |computeStackDepths|
pass, does all computations realted to variable names and stores the
results in the AST. Note that some knowledge about variables
(inevitably) remained in emitter code templates.
Beside DRYing things up, this change simplifies the emitter
significantly. By storing variable names in the AST it also allows
introduction of a pass that will identify parameters passed to actions
using proper symbol tables. Right now, this is done in a hackish way
directly in the emitter, which won't work well with changes planned in
GH-69.
Fixes the following JSHint errors:
./src/emitter.js: line 95, col 21, 'name' is already defined.
./src/emitter.js: line 361, col 35, 'setReportFailuresCode' is already defined.
./src/emitter.js: line 362, col 39, 'restoreReportFailuresCode' is already defined.
./src/emitter.js: line 363, col 31, 'reportFailureCode' is already defined.
./src/emitter.js: line 393, col 38, 'setReportFailuresCode' used out of scope.Fixes the following JSHint errors:
./src/emitter.js: line 394, col 38, 'restoreReportFailuresCode' used out of scope.
./src/emitter.js: line 395, col 38, 'reportFailureCode' used out of scope.
./src/emitter.js: line 666, col 26, 'formalParams' is already defined.
./src/emitter.js: line 667, col 26, 'actualParams' is already defined.
./src/emitter.js: line 669, col 26, 'formalParams' is already defined.
./src/emitter.js: line 670, col 26, 'actualParams' is already defined.
./src/emitter.js: line 685, col 27, 'formalParams' used out of scope.
./src/emitter.js: line 686, col 27, 'actualParams' used out of scope.
./src/emitter.js: line 770, col 20, 'regexp' is already defined.
./src/emitter.js: line 784, col 22, 'regexp' used out of scope.
David Majda