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-rw-r--r--ltn012.wiki6
-rw-r--r--ltn013.wiki6
2 files changed, 7 insertions, 5 deletions
diff --git a/ltn012.wiki b/ltn012.wiki
index b924dd3..96b13ae 100644
--- a/ltn012.wiki
+++ b/ltn012.wiki
@@ -126,8 +126,9 @@ local function chain2(f1, f2)
126end 126end
127 127
128function filter.chain(...) 128function filter.chain(...)
129 local arg = {...}
129 local f = arg[1] 130 local f = arg[1]
130 for i = 2, table.getn(arg) do 131 for i = 2, #arg do
131 f = chain2(f, arg[i]) 132 f = chain2(f, arg[i])
132 end 133 end
133 return f 134 return f
@@ -235,9 +236,10 @@ end
235We can make these ideas even more powerful if we use a new feature of Lua 5.0: coroutines. Coroutines suffer from a great lack of advertisement, and I am going to play my part here. Just like lexical scoping, coroutines taste odd at first, but once you get used with the concept, it can save your day. I have to admit that using coroutines to implement our file source would be overkill, so let's implement a concatenated source factory instead. 236We can make these ideas even more powerful if we use a new feature of Lua 5.0: coroutines. Coroutines suffer from a great lack of advertisement, and I am going to play my part here. Just like lexical scoping, coroutines taste odd at first, but once you get used with the concept, it can save your day. I have to admit that using coroutines to implement our file source would be overkill, so let's implement a concatenated source factory instead.
236 {{{ 237 {{{
237function source.cat(...) 238function source.cat(...)
239 local arg = {...}
238 local co = coroutine.create(function() 240 local co = coroutine.create(function()
239 local i = 1 241 local i = 1
240 while i <= table.getn(arg) do 242 while i <= #arg do
241 local chunk, err = arg[i]() 243 local chunk, err = arg[i]()
242 if chunk then coroutine.yield(chunk) 244 if chunk then coroutine.yield(chunk)
243 elseif err then return nil, err 245 elseif err then return nil, err
diff --git a/ltn013.wiki b/ltn013.wiki
index 734b433..a622424 100644
--- a/ltn013.wiki
+++ b/ltn013.wiki
@@ -73,12 +73,12 @@ Fortunately, all these problems are very easy to solve and that's what we do in
73We used the {{pcall}} function to shield the user from errors that could be raised by the underlying implementation. Instead of directly using {{pcall}} (and thus duplicating code) every time we prefer a factory that does the same job: 73We used the {{pcall}} function to shield the user from errors that could be raised by the underlying implementation. Instead of directly using {{pcall}} (and thus duplicating code) every time we prefer a factory that does the same job:
74 {{{ 74 {{{
75local function pack(ok, ...) 75local function pack(ok, ...)
76 return ok, arg 76 return ok, {...}
77end 77end
78 78
79function protect(f) 79function protect(f)
80 return function(...) 80 return function(...)
81 local ok, ret = pack(pcall(f, unpack(arg))) 81 local ok, ret = pack(pcall(f, ...))
82 if ok then return unpack(ret) 82 if ok then return unpack(ret)
83 else return nil, ret[1] end 83 else return nil, ret[1] end
84 end 84 end
@@ -157,7 +157,7 @@ function newtry(f)
157 if f then f() end 157 if f then f() end
158 error(arg[2], 0) 158 error(arg[2], 0)
159 else 159 else
160 return unpack(arg) 160 return ...
161 end 161 end
162 end 162 end
163end 163end