diff options
Diffstat (limited to 'lib/control_flow.nom')
| -rw-r--r-- | lib/control_flow.nom | 78 |
1 files changed, 48 insertions, 30 deletions
diff --git a/lib/control_flow.nom b/lib/control_flow.nom index ade9b42..240de17 100644 --- a/lib/control_flow.nom +++ b/lib/control_flow.nom @@ -9,10 +9,6 @@ immediately: \(%if_body as lua statements) end --end if parse [unless %condition %unless_body] as: if (not %condition) %unless_body - parse [if %x == %y %if_body] as: if (%x == %y) %if_body - parse [if %x != %y %if_body] as: if (%x != %y) %if_body - parse [unless %x == %y %if_body] as: if (%x != %y) %if_body - parse [unless %x != %y %if_body] as: if (%x == %y) %if_body compile [if %condition %if_body else %else_body, unless %condition %else_body else %if_body] to code: ".." if \(%condition as lua) then @@ -20,10 +16,6 @@ immediately: else \(%else_body as lua statements) end --end if - parse [if %x == %y %if_body else %else_body] as: if (%x == %y) %if_body else %else_body - parse [if %x != %y %if_body else %else_body] as: if (%x != %y) %if_body else %else_body - parse [unless %x == %y %if_body else %else_body] as: if (%x != %y) %if_body else %else_body - parse [unless %x != %y %if_body else %else_body] as: if (%x == %y) %if_body else %else_body # Return immediately: @@ -37,6 +29,11 @@ immediately: compile [go to %label] to code: ".." goto label_\(nomsu "var_to_lua_identifier" [%label]); +# Basic loop control +immediately: + compile [do next] to code: "continue;" + compile [stop] to code: "break;" + # Helper function immediately: action [tree %tree has function call %call]: @@ -71,10 +68,6 @@ immediately: return %code parse [repeat %body] as: repeat while (true) %body parse [repeat until %condition %body] as: repeat while (not %condition) %body - parse [repeat while %x == %y %body] as: repeat while (%x == %y) %body - parse [repeat while %x != %y %body] as: repeat while (%x != %y) %body - parse [repeat until %x == %y %body] as: repeat while (%x != %y) %body - parse [repeat until %x != %y %body] as: repeat while (%x == %y) %body # For loop control flow: immediately: @@ -115,7 +108,7 @@ immediately: \%code\ ..\%stop_labels end --for-loop label scope - ..if %stop_labels != "" else %code + ..if (%stop_labels is not "") else %code immediately: parse [for %var from %start to %stop %body] as: for %var from %start to %stop via 1 %body @@ -145,7 +138,7 @@ immediately: %stop_labels join= "\n::stop_for::;" if (tree %body has function call (tree \(stop %) with {""=%var})): %stop_labels join= "\n::stop_\(nomsu "var_to_lua_identifier" [%var])::;" - if %stop_labels != "": + if (%stop_labels is not ""): set %code = ".." do --for-loop label scope \%code\%stop_labels @@ -153,6 +146,31 @@ immediately: return %code parse [for all %iterable %body] as: for % in %iterable %body +immediately: + compile [..] + repeat %n times %body, repeat %n x %body + ..to code: + lua> "local \%continue_labels, \%code, \%stop_labels" + set %continue_labels = "" + if (tree %body has function call \(do next repeat-loop)): + %continue_labels join= "\n::continue_repeat::;" + # This trashes the loop variables, just like in Python. + set %code = ".." + for i=1,\(%n as lua) do + \(%body as lua statements)\ + ..\%continue_labels + end --numeric for-loop + set %stop_labels = "" + if (tree %body has function call \(stop repeat-loop)): + %stop_labels join= "\n::stop_repeat::;" + return (..) + ".." + do --repeat-loop label scope + \%code\ + ..\%stop_labels + end --repeat-loop label scope + ..if (%stop_labels is not "") else %code + # Dict iteration (lua's "pairs()") immediately: compile [for %key = %value in %iterable %body] to code: @@ -183,7 +201,7 @@ immediately: \%code\ ..\%stop_labels end --for-loop label scope - ..if %stop_labels != "" else %code + ..if (%stop_labels is not "") else %code # Switch statement/multi-branch if immediately: @@ -194,19 +212,19 @@ immediately: set %first = (yes) for %func_call in (%body's "value"): lua> "local \%tokens, \%star, \%condition, \%action" - assert ((%func_call's "type") == "FunctionCall") ".." + assume ((%func_call's "type") == "FunctionCall") or barf ".." Invalid format for 'when' statement. Only '*' blocks are allowed. set %tokens = (%func_call's "value") set %star = (%tokens -> 1) - assert (=lua "\%star and \%star.type == 'Word' and \%star.value == '*'") ".." + assume (=lua "\%star and \%star.type == 'Word' and \%star.value == '*'") or barf ".." Invalid format for 'when' statement. Lines must begin with '*' set %condition = (%tokens -> 2) - assert %condition ".." + assume %condition or barf ".." Invalid format for 'when' statement. Lines must begin with '*' and have a condition or the word "else" set %action = (%tokens -> 3) - if (%action == (nil)): + if (%action is (nil)): lua do> "table.insert(\%fallthroughs, \%condition)" do next %func_call @@ -234,24 +252,24 @@ immediately: # Switch statement immediately: - compile [when %branch_value == ? %body] to code: + compile [when %branch_value = ? %body, when %branch_value is ? %body] to code: set %result = "" set %fallthroughs = [] set %first = (yes) for %func_call in (%body's "value"): - assert ((%func_call's "type") == "FunctionCall") ".." + assume ((%func_call's "type") is "FunctionCall") or barf ".." Invalid format for 'when' statement. Only '*' blocks are allowed. set %tokens = (%func_call's "value") set %star = (%tokens -> 1) - assert (=lua "\%star and \%star.type == 'Word' and \%star.value == '*'") ".." + assume (=lua "\%star and \%star.type == 'Word' and \%star.value == '*'") or barf ".." Invalid format for 'when' statement. Lines must begin with '*' set %condition = (%tokens -> 2) - assert %condition ".." + assume %condition or barf ".." Invalid format for 'when' statement. Lines must begin with '*' and have a condition or the word "else" set %action = (%tokens -> 3) - if (%action == (nil)): + if (%action is (nil)): lua> "table.insert(\%fallthroughs, \%condition)" do next %func_call @@ -275,11 +293,11 @@ immediately: if (%result != ""): set %result = ".." - do --when == ? + do --when % = ? local branch_value = \(%branch_value as lua);\ ..\%result end - end --when == ? + end --when % = ? return %result # Try/except @@ -304,13 +322,13 @@ immediately: end end parse [try %action] as: - try %action and if it succeeds: pass - ..or if it fails: pass + try %action and if it succeeds: do nothing + ..or if it fails: do nothing parse [try %action and if it fails %fallback] as: - try %action and if it succeeds: pass + try %action and if it succeeds: do nothing ..or if it fails %fallback parse [try %action and if it succeeds %success] as: - try %action and if it succeeds %success or if it fails: pass + try %action and if it succeeds %success or if it fails: do nothing # Do/finally: immediately: |