diff --git a/REFERENCE.md b/REFERENCE.md index bcead73..c3823d7 100644 --- a/REFERENCE.md +++ b/REFERENCE.md @@ -24,9 +24,9 @@ Another line. #### Checkpoints -When executing a piece of Anselme code, it will not directly modify the global state (i.e. the values of variables used by every script), but only locally, in this execution. +When executing a piece of Anselme code, your scripts will not directly modify the global state (i.e. the values of variables used by every script), but only locally, in its associated interpreter instance. Meaning that if you change a variable, its value will only be set in the local state, so the new value will be accessible from the current interpreter but not other interpreters, at least until the next checkpoint. Similarly, the first time your script reads a variable its value at this time is kept into the local state so it can not be affected by other scripts, at least until the next checkpoint. -Right after reaching a checkpoint line, Anselme will merge the local state with the global one, i.e., make every change accessible to other scripts. +Right after reaching a checkpoint line, Anselme will merge the local state with the global one, i.e., make every change accessible to other scripts, and get checkpointed changes from other scripts. ``` $ main @@ -51,7 +51,9 @@ $ parallel ~ main ``` -The purpose of this system is both to allow several scripts to run at the same time with an easy way to avoid interferences, and to make sure the global state is always in a consistent (and not in the middle of a calculation): since scripts can be interrupted at any time, when it is interrupted, anything that was changed between the last checkpoint and the interruption will be discarded. When running the script again, it will resume correctly at the last reached checkpoint. See [function calls](#function-calls) for more details on how to call/resume a function. +The purpose of this system is both to allow several scripts to run at the same time with an easy way to avoid interferences, and to make sure the global state is always in a consistent (and not in the middle of a calculation): since scripts can be interrupted at any time, when it is interrupted, anything that was changed between the last checkpoint and the interruption will be discarded. If you're a RDBMS person, that's more-or-less equivalent to a transaction with a repeatable read isolation level (without any sort of locking or lost update protection though). + +When running the script again, it will resume correctly at the last reached checkpoint. See [function calls](#function-calls) for more details on how to call/resume a function. Checkpoints are set per function, and are expected to be defined inside functions only. diff --git a/anselme.lua b/anselme.lua index 9962c01..45f4df6 100644 --- a/anselme.lua +++ b/anselme.lua @@ -6,11 +6,11 @@ local anselme = { -- api is incremented a each update which may break Lua API compatibility versions = { save = 1, - language = 18, - api = 2 + language = 19, + api = 3 }, -- version is incremented at each update - version = 19, + version = 20, --- currently running interpreter running = nil } @@ -60,6 +60,25 @@ local function is_file(path) end end +--- recursively copy a table, handle cyclic references, no metatable +local function copy(t, cache) + if type(t) == "table" then + cache = cache or {} + if cache[t] then + return cache[t] + else + local c = {} + cache[t] = c + for k, v in pairs(t) do + c[k] = copy(v, cache) + end + return c + end + else + return t + end +end + --- interpreter methods local interpreter_methods = { -- interpreter state @@ -474,7 +493,16 @@ local vm_mt = { builtin_aliases = self.state.builtin_aliases, aliases = setmetatable({}, { __index = self.state.aliases }), functions = self.state.functions, -- no need for a cache as we can't define or modify any function from the interpreter for now - variables = setmetatable({}, { __index = self.state.variables }), + variables = setmetatable({}, { + __index = function(variables, k) + local cache = getmetatable(variables).cache + if cache[k] == nil then + cache[k] = copy(self.state.variables[k]) + end + return cache[k] + end, + cache = {} -- cache of previously read values, to get repeatable reads & handle mutable types without changing global state + }), interpreter = { -- constant global_state = self.state, diff --git a/interpreter/common.lua b/interpreter/common.lua index 2028885..679d8ae 100644 --- a/interpreter/common.lua +++ b/interpreter/common.lua @@ -32,11 +32,23 @@ local common common = { --- merge interpreter state with global state merge_state = function(state) + -- merge alias state local global = state.interpreter.global_state for alias, fqm in pairs(state.aliases) do global.aliases[alias] = fqm state.aliases[alias] = nil end + -- variable state + -- move values modifed in-place from read cache to variables + local cache = getmetatable(state.variables).cache + for var, value in pairs(cache) do + if value.modified then + value.modified = nil + state.variables[var] = value + end + cache[var] = nil + end + -- merge modified variables for var, value in pairs(state.variables) do global.variables[var] = value state.variables[var] = nil diff --git a/stdlib/functions.lua b/stdlib/functions.lua index 2343e4d..7b2bf5c 100644 --- a/stdlib/functions.lua +++ b/stdlib/functions.lua @@ -91,6 +91,7 @@ functions = { ["()(l::list, i::number) := v"] = { mode = "raw", value = function(l, i, v) + l.modified = true local lv = l.type == "type" and l.value[1] or l local iv = i.type == "type" and i.value[1] or i lv.value[iv.value] = v @@ -100,6 +101,7 @@ functions = { ["()(l::list, k::string) := v"] = { mode = "raw", value = function(l, k, v) + l.modified = true local lv = l.type == "type" and l.value[1] or l local kv = k.type == "type" and k.value[1] or k -- update index @@ -168,27 +170,33 @@ functions = { ["insert(l::list, v)"] = { mode = "raw", value = function(l, v) + l.modified = true local lv = l.type == "type" and l.value[1] or l table.insert(lv.value, v) + return l end }, ["insert(l::list, i::number, v)"] = { mode = "raw", value = function(l, i, v) + l.modified = true local lv = l.type == "type" and l.value[1] or l local iv = i.type == "type" and i.value[1] or i table.insert(lv.value, iv.value, v) + return l end }, ["remove(l::list)"] = { mode = "untyped raw", value = function(l) + l.modified = true return table.remove(l.value) end }, ["remove(l::list, i::number)"] = { mode = "untyped raw", value = function(l, i) + l.modified = true return table.remove(l.value, i.value) end }, diff --git a/test/run.lua b/test/run.lua index 2e4f508..ae6e1af 100644 --- a/test/run.lua +++ b/test/run.lua @@ -195,6 +195,19 @@ else local t, d = istate:step() table.insert(result, { t, d }) until t == "return" or t == "error" + + local postrun = vm:eval(namespace..".post run") + if postrun then + istate, e = vm:run(namespace.."."..postrun) + if not istate then + table.insert(result, { "error", e }) + else + repeat + local t, d = istate:step() + table.insert(result, { t, d }) + until t == "return" or t == "error" + end + end end else table.insert(result, { "error", err }) diff --git a/test/tests/checkpoint merging mutable value.ans b/test/tests/checkpoint merging mutable value.ans new file mode 100644 index 0000000..65c0489 --- /dev/null +++ b/test/tests/checkpoint merging mutable value.ans @@ -0,0 +1,26 @@ +:post run = "after error" + +:l = [1,2] + +1,2: {l} + +~ l.insert(3) + +1,2,3: {l} + +§ a + +~ l.insert(4) + +1,2,3,4: {l} + +§ b + +~ l.insert(5) + +1,2,3,4,5: {l} + +~ error("cancel merge") + +$ after error + 1,2,3,4: {l} diff --git a/test/tests/checkpoint merging mutable value.lua b/test/tests/checkpoint merging mutable value.lua new file mode 100644 index 0000000..076460b --- /dev/null +++ b/test/tests/checkpoint merging mutable value.lua @@ -0,0 +1,68 @@ +local _={} +_[27]={} +_[26]={} +_[25]={} +_[24]={} +_[23]={} +_[22]={tags=_[27],text="[1, 2, 3, 4]"} +_[21]={tags=_[27],text="1,2,3,4: "} +_[20]={tags=_[26],text="[1, 2, 3, 4, 5]"} +_[19]={tags=_[26],text="1,2,3,4,5: "} +_[18]={tags=_[25],text="[1, 2, 3, 4]"} +_[17]={tags=_[25],text="1,2,3,4: "} +_[16]={tags=_[24],text="[1, 2, 3]"} +_[15]={tags=_[24],text="1,2,3: "} +_[14]={tags=_[23],text="[1, 2]"} +_[13]={tags=_[23],text="1,2: "} +_[12]={_[21],_[22]} +_[11]={_[19],_[20]} +_[10]={_[17],_[18]} +_[9]={_[15],_[16]} +_[8]={_[13],_[14]} +_[7]={"return"} +_[6]={"text",_[12]} +_[5]={"error","cancel merge; in Lua function \"error\"; at test/tests/checkpoint merging mutable value.ans:23"} +_[4]={"text",_[11]} +_[3]={"text",_[10]} +_[2]={"text",_[9]} +_[1]={"text",_[8]} +return {_[1],_[2],_[3],_[4],_[5],_[6],_[7]} +--[[ +{ "text", { { + tags = <1>{}, + text = "1,2: " + }, { + tags = , + text = "[1, 2]" + } } } +{ "text", { { + tags = <1>{}, + text = "1,2,3: " + }, { + tags =
, + text = "[1, 2, 3]" + } } } +{ "text", { { + tags = <1>{}, + text = "1,2,3,4: " + }, { + tags =
, + text = "[1, 2, 3, 4]" + } } } +{ "text", { { + tags = <1>{}, + text = "1,2,3,4,5: " + }, { + tags =
, + text = "[1, 2, 3, 4, 5]" + } } } +{ "error", 'cancel merge; in Lua function "error"; at test/tests/checkpoint merging mutable value.ans:23' } +{ "text", { { + tags = <1>{}, + text = "1,2,3,4: " + }, { + tags =
, + text = "[1, 2, 3, 4]" + } } } +{ "return" } +]]-- \ No newline at end of file diff --git a/test/tests/checkpoint merging variable.ans b/test/tests/checkpoint merging variable.ans new file mode 100644 index 0000000..c2d6136 --- /dev/null +++ b/test/tests/checkpoint merging variable.ans @@ -0,0 +1,26 @@ +:post run = "after error" + +:l = 1 + +1: {l} + +~ l := 2 + +2: {l} + +§ a + +~ l := 3 + +3: {l} + +§ b + +~ l := 4 + +4: {l} + +~ error("cancel merge") + +$ after error + 3: {l} diff --git a/test/tests/checkpoint merging variable.lua b/test/tests/checkpoint merging variable.lua new file mode 100644 index 0000000..c471455 --- /dev/null +++ b/test/tests/checkpoint merging variable.lua @@ -0,0 +1,68 @@ +local _={} +_[27]={} +_[26]={} +_[25]={} +_[24]={} +_[23]={} +_[22]={tags=_[27],text="3"} +_[21]={tags=_[27],text="3: "} +_[20]={tags=_[26],text="4"} +_[19]={tags=_[26],text="4: "} +_[18]={tags=_[25],text="3"} +_[17]={tags=_[25],text="3: "} +_[16]={tags=_[24],text="2"} +_[15]={tags=_[24],text="2: "} +_[14]={tags=_[23],text="1"} +_[13]={tags=_[23],text="1: "} +_[12]={_[21],_[22]} +_[11]={_[19],_[20]} +_[10]={_[17],_[18]} +_[9]={_[15],_[16]} +_[8]={_[13],_[14]} +_[7]={"return"} +_[6]={"text",_[12]} +_[5]={"error","cancel merge; in Lua function \"error\"; at test/tests/checkpoint merging variable.ans:23"} +_[4]={"text",_[11]} +_[3]={"text",_[10]} +_[2]={"text",_[9]} +_[1]={"text",_[8]} +return {_[1],_[2],_[3],_[4],_[5],_[6],_[7]} +--[[ +{ "text", { { + tags = <1>{}, + text = "1: " + }, { + tags =
, + text = "1" + } } } +{ "text", { { + tags = <1>{}, + text = "2: " + }, { + tags =
, + text = "2" + } } } +{ "text", { { + tags = <1>{}, + text = "3: " + }, { + tags =
, + text = "3" + } } } +{ "text", { { + tags = <1>{}, + text = "4: " + }, { + tags =
, + text = "4" + } } } +{ "error", 'cancel merge; in Lua function "error"; at test/tests/checkpoint merging variable.ans:23' } +{ "text", { { + tags = <1>{}, + text = "3: " + }, { + tags =
, + text = "3" + } } } +{ "return" } +]]-- \ No newline at end of file