diff options
Diffstat (limited to 'lib/control_flow.nom')
| -rw-r--r-- | lib/control_flow.nom | 143 |
1 files changed, 66 insertions, 77 deletions
diff --git a/lib/control_flow.nom b/lib/control_flow.nom index 460d4dc..4e13a8c 100644 --- a/lib/control_flow.nom +++ b/lib/control_flow.nom @@ -3,73 +3,60 @@ require "lib/operators.nom" require "lib/utils.nom" # Conditionals -parse (if %condition %if_body) as lua code ".." - |if \(%condition) then - | \(lua expr "vars.if_body.value") +compile (if %condition %if_body) to code: ".." + |if \(%condition as lua) then + | \(%if_body as lua statements) |end -parse (if %condition %if_body else %else_body) as lua code ".." - |if \(%condition) then - | \(lua expr "vars.if_body.value") +compile (if %condition %if_body else %else_body) to code: ".." + |if \(%condition as lua) then + | \(%if_body as lua statements) |else - | \(lua expr "vars.else_body.value") + | \(%else_body as lua statements) |end # Return -parse (return) as lua code "do return end" -parse (return %return-value) as lua code "do return \(%return-value)" -parse (do %action) as lua expr ".." - |(\(%action))(nomsu, setmetatable({}, {__index=vars})) - +compile (return) to code: "do return end" +compile (return %return-value) to code: "do return \(%return-value as lua) end" # GOTOs -parse (-> %label) as lua code ".." +compile (-> %label) to code: ".." |::label_\(nomsu "var_to_lua_identifier" [%label]):: -parse (go to %label) as lua code ".." +compile (go to %label) to code: ".." |goto label_\(nomsu "var_to_lua_identifier" [%label]) # Loop control flow -parse (stop; stop loop; break) as lua code "break" -parse (stop for; stop for-loop; break for) as lua code "goto break_for" -parse (stop repeat; stop repeat-loop; break repeat) as lua code "goto break_repeat" -parse (stop %var; break %var) as lua code ".." +compile (stop; stop loop; break) to code: "break" +compile (stop for; stop for-loop; break for) to code: "goto break_for" +compile (stop repeat; stop repeat-loop; break repeat) to code: "goto break_repeat" +compile (stop %var; break %var) to code: ".." |goto break_\(nomsu "var_to_lua_identifier" [%var]) -parse (continue; continue loop) as lua code "continue" -parse (continue for; continue for-loop) as lua code "goto continue_for" -parse (continue repeat; continue repeat-loop) as lua code "goto continue_repeat" -parse (continue %var; go to next %var; on to the next %var) as lua code ".." +compile (continue; continue loop) to code: "continue" +compile (continue for; continue for-loop) to code: "goto continue_for" +compile (continue repeat; continue repeat-loop) to code: "goto continue_repeat" +compile (continue %var; go to next %var; on to the next %var) to code: ".." |goto continue_\(nomsu "var_to_lua_identifier" [%var]) # While loops -parse (repeat %body) as lua block ".." - |while true do - | \(lua expr "vars.body.value") - | ::continue_repeat:: - |end - |::break_repeat:: -parse (repeat while %condition %body) as lua block ".." +compile (repeat while %condition %body) to block: ".." |while \(%condition) do - | \(lua expr "vars.body.value") - | ::continue_repeat:: - |end - |::break_repeat:: -parse (repeat until %condition %body) as lua block ".." - |while not (\(%condition)) do - | \(lua expr "vars.body.value") + | \(%body as lua statements) | ::continue_repeat:: |end |::break_repeat:: +parse (repeat %body) as: repeat while (true) %body +parse (repeat until %condition %body) as: repeat while (not %condition) %body # Numeric range for loops -parse: +compile: for %var from %start to %stop by %step %body for %var from %start to %stop via %step %body -..as lua block ".." - |for i=\(%start),\(%stop),\(%step) do +..to block: ".." + |for i=\(%start as lua),\(%stop as lua),\(%step as lua) do # This trashes the loop variables, just like in Python. - | \(%var) = i - | \(lua expr "vars.body.value") + | \(%var as lua) = i + | \(%body as lua statements) | ::continue_for:: | ::continue_\(nomsu "var_to_lua_identifier" [%var]):: |end @@ -82,38 +69,39 @@ parse: ..as: for % from %start to %stop via %step %body parse (for all %start to %stop %body) as: for all %start to %stop via 1 %body -parse (for %var in %iterable %body) as lua block ".." - |for i,value in ipairs(\(%iterable)) do - # This trashes the loop variables, just like in Python. - | \(%var) = value - | \(lua expr "vars.body.value") - | ::continue_for:: - | ::continue_\(nomsu "var_to_lua_identifier" [%var]):: - |end - |::break_for:: - |::break_\(nomsu "var_to_lua_identifier" [%var]):: +compile (for %var in %iterable %body) to block: + ".." + |for i,value in ipairs(\(%iterable as lua)) do + # This trashes the loop variables, just like in Python. + | \(%var as lua) = value + | \(%body as lua statements) + | ::continue_for:: + | ::continue_\(nomsu "var_to_lua_identifier" [%var]):: + |end + |::break_for:: + |::break_\(nomsu "var_to_lua_identifier" [%var]):: parse (for all %iterable %body) as: for % in %iterable %body + # Switch statement/multi-branch if -parse (when %body) as lua block: +compile (when %body) to block: %result =: "" %fallthroughs =: [] - for %statement in (lua expr "vars.body.value.value"): - %func-call =: lua expr "vars.statement.value" - assert ((lua expr "vars['func-call'].type") == "FunctionCall") ".." + for %statement in (%body's "value"): + %func-call =: %statement's "value" + assert ((%func-call's "type") == "FunctionCall") ".." |Invalid format for 'when' statement. Only '*' blocks are allowed. - %tokens =: lua expr "vars['func-call'].value" - - %star =: lua expr "vars.tokens[1]" + %tokens =: %func-call's "value" + %star =: %tokens -> 1 assert (lua expr "vars.star and vars.star.type == 'Word' and vars.star.value == '*'") ".." |Invalid format for 'when' statement. Lines must begin with '*' - %condition =: lua expr "vars.tokens[2]" + %condition =: %tokens -> 2 assert %condition ".." |Invalid format for 'when' statement. Lines must begin with '*' and have a condition or the word "else" - %thunk =: lua expr "vars.tokens[3]" - if (%thunk == (nil)): + %action =: %tokens -> 3 + if (%action == (nil)): lua block "table.insert(vars.fallthroughs, vars.condition)" go to next %statement @@ -123,13 +111,14 @@ parse (when %body) as lua block: |do ..else: %condition =: %condition as lua - for all %fallthroughs: %condition join= " or \(%)" + for all %fallthroughs: + %condition join=: " or \(% as lua)" %result join=: ".." | |if \(%condition) then %result join=: ".." | - | \(lua expr "vars.thunk.value") + | \(%action as lua statements) | goto finished_when |end @@ -139,25 +128,24 @@ parse (when %body) as lua block: %result # Switch statement -parse (when %branch-value == ? %body) as lua block: +compile (when %branch-value == ? %body) to block: %result =: "local branch_value = \(%branch-value)" %fallthroughs =: [] - for %statement in (lua expr "vars.body.value.value"): - %func-call =: lua expr "vars.statement.value" - assert ((lua expr "vars['func-call'].type") == "FunctionCall") ".." + for %statement in (%body's "value"): + %func-call =: %statement's "value" + assert ((%func-call's "type") == "FunctionCall") ".." |Invalid format for 'when' statement. Only '*' blocks are allowed. - %tokens =: lua expr "vars['func-call'].value" - - %star =: lua expr "vars.tokens[1]" + %tokens =: %func-call's "value" + %star =: %tokens -> 1 assert (lua expr "vars.star and vars.star.type == 'Word' and vars.star.value == '*'") ".." |Invalid format for 'when' statement. Lines must begin with '*' - %condition =: lua expr "vars.tokens[2]" + %condition =: %tokens -> 2 assert %condition ".." |Invalid format for 'when' statement. Lines must begin with '*' and have a condition or the word "else" - %thunk =: lua expr "vars.tokens[3]" - if (%thunk == (nil)): + %action =: %tokens -> 3 + if (%action == (nil)): lua block "table.insert(vars.fallthroughs, vars.condition)" go to next %statement @@ -166,14 +154,15 @@ parse (when %branch-value == ? %body) as lua block: | |do ..else: - %condition =: "branch_value == (\(%condition))" - for all %fallthroughs: %condition join= " or (branch_value == \(%))" + %condition =: "branch_value == (\(%condition as lua))" + for all %fallthroughs: + %condition join=: " or (branch_value == \(% as lua))" %result join=: ".." | - |if \%condition\ then + |if \(%condition) then %result join=: ".." | - | \((lua expr "vars.thunk.value")) + | \(%action as lua statements) | goto finished_when |end |