Sexp

Sexps are the basic storage mechanism of SexpProcessor. Sexps have a type (to be renamed node_type) which is the first element of the Sexp. The type is used by SexpProcessor to determine whom to dispatch the Sexp to for processing.

Attributes

line[W]

file[RW]

comments[RW]

Public Class Methods

from_array(a) click to toggle source

Creates a new Sexp from Array a.

    # File lib/sexp.rb, line 27
27:   def self.from_array(a)
28:     ary = Array === a ? a : [a]
29: 
30:     result = self.new
31: 
32:     ary.each do |x|
33:       case x
34:       when Sexp
35:         result << x
36:       when Array
37:         result << self.from_array(x)
38:       else
39:         result << x
40:       end
41:     end
42: 
43:     result
44:   end

new(*args) click to toggle source

Create a new Sexp containing args.

    # File lib/sexp.rb, line 20
20:   def initialize(*args)
21:     super(args)
22:   end

Public Instance Methods

===(sexp) click to toggle source

Returns true if this Sexp’s pattern matches sexp.

    # File lib/sexp.rb, line 57
57:   def ===(sexp)
58:     return nil unless Sexp === sexp
59:     pattern = self # this is just for my brain
60: 
61:     return true if pattern == sexp
62: 
63:     sexp.each do |subset|
64:       return true if pattern === subset
65:     end
66: 
67:     return nil
68:   end

=~(pattern) click to toggle source

Returns true if this Sexp matches pattern. (Opposite of #===.)

    # File lib/sexp.rb, line 73
73:   def =~(pattern)
74:     return pattern === self
75:   end

array_type?() click to toggle source

Returns true if the node_type is array or args.

REFACTOR: to TypedSexp - we only care when we have units.

    # File lib/sexp.rb, line 82
82:   def array_type?
83:     type = self.first
84:     @@array_types.include? type
85:   end

each_of_type(t, &b) click to toggle source

Enumeratates the sexp yielding to b when the node_type == t.

     # File lib/sexp.rb, line 94
 94:   def each_of_type(t, &b)
 95:     each do | elem |
 96:       if Sexp === elem then
 97:         elem.each_of_type(t, &b)
 98:         b.call(elem) if elem.first == t
 99:       end
100:     end
101:   end

find_and_replace_all(from, to) click to toggle source

Replaces all elements whose node_type is from with to. Used only for the most trivial of rewrites.

     # File lib/sexp.rb, line 107
107:   def find_and_replace_all(from, to)
108:     each_with_index do | elem, index |
109:       if Sexp === elem then
110:         elem.find_and_replace_all(from, to)
111:       else
112:         self[index] = to if elem == from
113:       end
114:     end
115:   end

find_node(name, delete = false) click to toggle source

     # File lib/sexp.rb, line 144
144:   def find_node name, delete = false
145:     matches = find_nodes name
146: 
147:     case matches.size
148:     when 0 then
149:       nil
150:     when 1 then
151:       match = matches.first
152:       delete match if delete
153:       match
154:     else
155:       raise NoMethodError, "multiple nodes for #{name} were found in #{inspect}"
156:     end
157:   end

find_nodes(name) click to toggle source

Find every node with type name.

     # File lib/sexp.rb, line 162
162:   def find_nodes name
163:     find_all { | sexp | Sexp === sexp and sexp.first == name }
164:   end

gsub(pattern, repl) click to toggle source

Replaces all Sexps matching pattern with Sexp repl.

     # File lib/sexp.rb, line 120
120:   def gsub(pattern, repl)
121:     return repl if pattern == self
122: 
123:     new = self.map do |subset|
124:       case subset
125:       when Sexp then
126:         subset.gsub(pattern, repl)
127:       else
128:         subset
129:       end
130:     end
131: 
132:     return Sexp.from_array(new)
133:   end

line(n=nil) click to toggle source

If passed a line number, sets the line and returns self. Otherwise returns the line number. This allows you to do message cascades and still get the sexp back.

     # File lib/sexp.rb, line 171
171:   def line(n=nil)
172:     if n then
173:       @line = n
174:       self
175:     else
176:       @line ||= nil
177:     end
178:   end

mass() click to toggle source

Returns the size of the sexp, flattened.

     # File lib/sexp.rb, line 183
183:   def mass
184:     @mass ||= self.structure.flatten.size
185:   end

method_missing(meth, delete = false) click to toggle source

Returns the node named node, deleting it if delete is true.

     # File lib/sexp.rb, line 190
190:   def method_missing meth, delete = false
191:     find_node meth, delete
192:   end

sexp_body() click to toggle source

Returns the Sexp body, ie the values without the node type.

     # File lib/sexp.rb, line 213
213:   def sexp_body
214:     self[1..1]
215:   end

sexp_type() click to toggle source

Returns the node type of the Sexp.

     # File lib/sexp.rb, line 206
206:   def sexp_type
207:     first
208:   end

shift() click to toggle source

If run with debug, Sexp will raise if you shift on an empty Sexp. Helps with debugging.

     # File lib/sexp.rb, line 221
221:   def shift
222:     raise "I'm empty" if self.empty?
223:     super
224:   end

structure() click to toggle source

Returns the bare bones structure of the sexp. s(:a, :b, s(:c, :d), :e) => s(:a, s(:c))

     # File lib/sexp.rb, line 230
230:   def structure
231:     result = self.class.new
232:     if Array === self.first then
233:       result = self.first.structure
234:     else
235:       result << self.first
236:       self.grep(Array).each do |subexp|
237:         result << subexp.structure
238:       end
239:     end
240:     result
241:   end

sub(pattern, repl) click to toggle source

Replaces the Sexp matching pattern with repl.

     # File lib/sexp.rb, line 246
246:   def sub(pattern, repl)
247:     return repl.dup if pattern == self
248: 
249:     done = false
250: 
251:     new = self.map do |subset|
252:       if done then
253:         subset
254:       else
255:         case subset
256:         when Sexp then
257:           if pattern == subset then
258:             done = true
259:             repl.dup
260:           elsif pattern === subset then
261:             done = true
262:             subset.sub pattern, repl
263:           else
264:             subset
265:           end
266:         else
267:           subset
268:         end
269:       end
270:     end
271: 
272:     return Sexp.from_array(new)
273:   end

Home Classes Methods

In Files

Parent

Methods

Files

Class Index

Sexp

Attributes

Public Class Methods

Public Instance Methods