在Ada中初始化动态分配的数组的正确语法是什么？我试过这个：
C:/Ruby22/lib/ruby/gems/2.2.0/gems/bcrypt-3.1.11-x86-mingw32/lib/bcrypt/password.rb in initialize
raise Errors::InvalidHash.new("invalid hash")
C:/Ruby22/lib/ruby/gems/2.2.0/gems/mongoid-bcrypt-ruby-0.0.2/lib/mongoid/bcrypt/ruby.rb in new
when String then self.new(password)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/mongoid-bcrypt-ruby-0.0.2/lib/mongoid/bcrypt/ruby.rb in demongoize
when String then self.new(password)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/mongoid-6.0.2/lib/mongoid/fields/standard.rb in demongoize
delegate :demongoize, :evolve, :mongoize, to: :type
C:/Ruby22/lib/ruby/gems/2.2.0/gems/mongoid-6.0.2/lib/mongoid/fields.rb in block (2 levels) in create_field_getter
value = field.demongoize(raw)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/mongoid-6.0.2/lib/mongoid/validatable.rb in read_attribute_for_validation
send(attr)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activemodel-5.0.0.1/lib/active_model/validator.rb in block in validate
value = record.read_attribute_for_validation(attribute)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activemodel-5.0.0.1/lib/active_model/validator.rb in each
attributes.each do |attribute|
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activemodel-5.0.0.1/lib/active_model/validator.rb in validate
attributes.each do |attribute|
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in public_send
filter.public_send method_to_call, target, &blk
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in block in make_lambda
filter.public_send method_to_call, target, &blk
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in call
result_lambda = -> { user_callback.call target, value }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in block (2 levels) in halting
result_lambda = -> { user_callback.call target, value }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in call
result_lambda.call if result_lambda.is_a?(Proc)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in block (2 levels) in default_terminator
result_lambda.call if result_lambda.is_a?(Proc)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in catch
catch(:abort) do
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in block in default_terminator
catch(:abort) do
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in call
env.halted = halted_lambda.call(target, result_lambda)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in block in halting
env.halted = halted_lambda.call(target, result_lambda)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in call
@before.each { |b| b.call(arg) }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in block in call
@before.each { |b| b.call(arg) }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in each
@before.each { |b| b.call(arg) }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in call
@before.each { |b| b.call(arg) }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in __run_callbacks__
runner.call(e).value
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in _run_validate_callbacks
__run_callbacks__(_#{name}_callbacks, &block)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activemodel-5.0.0.1/lib/active_model/validations.rb in run_validations!
_run_validate_callbacks
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activemodel-5.0.0.1/lib/active_model/validations/callbacks.rb in block in run_validations!
_run_validation_callbacks { super }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in __run_callbacks__
yield if block_given?
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb in _run_validation_callbacks
__run_callbacks__(_#{name}_callbacks, &block)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activemodel-5.0.0.1/lib/active_model/validations/callbacks.rb in run_validations!
_run_validation_callbacks { super }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activemodel-5.0.0.1/lib/active_model/validations.rb in valid?
run_validations!
C:/Ruby22/lib/ruby/gems/2.2.0/gems/mongoid-6.0.2/lib/mongoid/validatable.rb in valid?
super context ? context : (new_record? ? :create : :update)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/activemodel-5.0.0.1/lib/active_model/validations.rb in invalid?
!valid?(context)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/mongoid-6.0.2/lib/mongoid/persistable/creatable.rb in prepare_insert
invalid?(options[:context] || :create)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/mongoid-6.0.2/lib/mongoid/persistable/creatable.rb in insert
prepare_insert(options) do
C:/Ruby22/lib/ruby/gems/2.2.0/gems/mongoid-6.0.2/lib/mongoid/persistable/creatable.rb in block in create!
doc.fail_due_to_validation! unless doc.insert.errors.empty?
C:/Ruby22/lib/ruby/gems/2.2.0/gems/mongoid-6.0.2/lib/mongoid/threaded/lifecycle.rb in _creating
yield
C:/Ruby22/lib/ruby/gems/2.2.0/gems/mongoid-6.0.2/lib/mongoid/persistable/creatable.rb in create!
_creating do
C:/Users/ALilland/Documents/macros/experiments/mongoid/mongoid_heroku/db_core_app/models/user.rb in block (2 levels) in <class:Routes>
User.create!(
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in call
proc { |a,p| unbound_method.bind(a).call }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in block in compile!
proc { |a,p| unbound_method.bind(a).call }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in []
route_eval { block[*args] }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in block (3 levels) in route!
route_eval { block[*args] }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in route_eval
throw :halt, yield
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in block (2 levels) in route!
route_eval { block[*args] }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in block in process_route
block ? block[self, values] : yield(self, values)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in catch
catch(:pass) do
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in process_route
catch(:pass) do
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in block in route!
returned_pass_block = process_route(pattern, keys, conditions) do |*args|
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in each
routes.each do |pattern, keys, conditions, block|
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in route!
routes.each do |pattern, keys, conditions, block|
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in block in dispatch!
route!
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in block in invoke
res = catch(:halt) { yield }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in catch
res = catch(:halt) { yield }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in invoke
res = catch(:halt) { yield }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in dispatch!
invoke do
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in block in call!
invoke { dispatch! }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in block in invoke
res = catch(:halt) { yield }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in catch
res = catch(:halt) { yield }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in invoke
res = catch(:halt) { yield }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in call!
invoke { dispatch! }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in call
dup.call!(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-protection-1.5.3/lib/rack/protection/xss_header.rb in call
status, headers, body = @app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-protection-1.5.3/lib/rack/protection/base.rb in call
result or app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-protection-1.5.3/lib/rack/protection/base.rb in call
result or app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-protection-1.5.3/lib/rack/protection/path_traversal.rb in call
app.call env
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-protection-1.5.3/lib/rack/protection/json_csrf.rb in call
status, headers, body = app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-protection-1.5.3/lib/rack/protection/base.rb in call
result or app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-protection-1.5.3/lib/rack/protection/base.rb in call
result or app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-protection-1.5.3/lib/rack/protection/frame_options.rb in call
status, headers, body = @app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/session/abstract/id.rb in context
status, headers, body = app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/session/abstract/id.rb in call
context(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/logger.rb in call
@app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in call
env['sinatra.commonlogger'] ? @app.call(env) : super
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/head.rb in call
status, headers, body = @app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/show_exceptions.rb in call
@app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in call
result, callback = app.call(env), env['async.callback']
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in call
@stack.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in block in call
synchronize { prototype.call(env) }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in synchronize
yield
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in call
synchronize { prototype.call(env) }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/cascade.rb in block in call
result = app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/cascade.rb in each
@apps.each do |app|
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/cascade.rb in call
@apps.each do |app|
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/tempfile_reaper.rb in call
status, headers, body = @app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/lint.rb in _call
status, headers, @body = @app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/lint.rb in call
dup._call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/showexceptions.rb in call
@app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/commonlogger.rb in call
status, header, body = @app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/sinatra-1.4.7/lib/sinatra/base.rb in call
call_without_check(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/chunked.rb in call
status, headers, body = @app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/content_length.rb in call
status, headers, body = @app.call(env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/thin-1.7.0/lib/thin/connection.rb in block in pre_process
response = @app.call(@request.env)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/thin-1.7.0/lib/thin/connection.rb in catch
catch(:async) do
C:/Ruby22/lib/ruby/gems/2.2.0/gems/thin-1.7.0/lib/thin/connection.rb in pre_process
catch(:async) do
C:/Ruby22/lib/ruby/gems/2.2.0/gems/thin-1.7.0/lib/thin/connection.rb in process
post_process(pre_process)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/thin-1.7.0/lib/thin/connection.rb in receive_data
process if @request.parse(data)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/eventmachine-1.2.1-x86-mingw32/lib/eventmachine.rb in run_machine
run_machine
C:/Ruby22/lib/ruby/gems/2.2.0/gems/eventmachine-1.2.1-x86-mingw32/lib/eventmachine.rb in run
run_machine
C:/Ruby22/lib/ruby/gems/2.2.0/gems/thin-1.7.0/lib/thin/backends/base.rb in start
EventMachine.run(&starter)
C:/Ruby22/lib/ruby/gems/2.2.0/gems/thin-1.7.0/lib/thin/server.rb in start
@backend.start { setup_signals if @setup_signals }
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/handler/thin.rb in run
server.start
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/server.rb in start
server.run wrapped_app, options, &blk
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/lib/rack/server.rb in start
new(options).start
C:/Ruby22/lib/ruby/gems/2.2.0/gems/rack-1.6.5/bin/rackup in <top (required)>
Rack::Server.start
C:/Ruby22/bin/rackup in load
load Gem.bin_path('rack', 'rackup', version)
C:/Ruby22/bin/rackup in <main>
load Gem.bin_path('rack', 'rackup', version)
导致编译器错误 - “二元运算符预期”。这个：
type Short_Array is array (Natural range <>) of Short;
Items : access Short_Array;
Items := new Short_Array(1..UpperBound)'(others => 0);
这似乎令人惊讶地提升了一个SEGFAULT。不确定那里发生了什么，但想在我开始追逐我的尾巴之前获得正确的语法。
答案 0 :(得分：5)
如果您使用的是Ada2012，则可以执行以下操作：
type Short_Array is array(Natural range <>) of Short with
Default_Component_Value => 0;
Items : access Short_Array := new Short_Array(1..UpperBound);
在Ada 2012 Rationale http://www.ada-auth.org/standards/12rat/html/Rat12-2-6.html
的第2.6节中解释了数组的默认初始值的使用答案 1 :(得分：3)
Ada的另一种方法是将记录定义为判别式记录，判别式确定数组字段的大小。
type Items_Record (Size : Natural) is record
-- Some non-array fields of your record
Items : Short_Array(1..Size);
end record;
然后可以在内部块
中分配记录的实例Get(Items_Size);
declare
My_Record : Items_Record(Size => Items_Size);
begin
-- Process the instance of Items_Record
end;
记录在堆栈上动态分配。如果记录大小非常大，您将遇到堆栈溢出问题。如果没有，这非常有效。这种方法的一个优点是，当到达块的末尾时，实例会自动解除分配。
答案 2 :(得分：0)
第二个示例中的SEGFAULT最有可能来自初始化。
比较
type Short_Array is array (Natural range <>) of Short;
Items : access Short_Array;
Items := new Short_Array(1..UpperBound);
Items.all := (others => 0);
这：
type Short_Array is array (Natural range <>) of Short;
Items : access Short_Array;
Items := new Short_Array(1..UpperBound);
for I in 1..UpperBound loop
Items(I) := 0;
end loop;
并使用ulimit -Ss的不同值进行设置，以设置允许的堆栈大小。
重点是
Items.all := (others => 0);
在堆栈上分配一个数组，并将其复制到堆分配的数组中。因此，您认为您正在堆上工作，但仍需要大量堆栈。如果您的数组对于您的ulimit -Ss太大（或同时考虑软限制和硬限制ulimit -s），则尽管您认为自己都在堆上，但仍会发生段错误（或得到STORAGE_ERROR）
为缓解此问题，（尽管在UpperBound是动态的情况下可能无法在每种情况下使用 eg …），您可以使用以下方法编译代码：
"-fstack-usage"（获取每个单元的使用信息）"-Wstack-usage=2000"（或根据您的情况更准确的限制，请参见gnat's documentation，以获取更多信息），以警告使用过多堆栈（或堆栈使用量不受限制）的函数。第二个选项可能已发出警告，并指出堆栈溢出。