diff options
Diffstat (limited to 'lib/core/control_flow.nom')
| -rw-r--r-- | lib/core/control_flow.nom | 65 |
1 files changed, 36 insertions, 29 deletions
diff --git a/lib/core/control_flow.nom b/lib/core/control_flow.nom index 21e0618..fafc45d 100644 --- a/lib/core/control_flow.nom +++ b/lib/core/control_flow.nom @@ -42,8 +42,8 @@ test: (else $) compiles to: at (this tree) fail (" Compile error: This 'else' is not connected to any 'if' or 'unless' condition. - Hint: You should probably have a ".." in front of the "else", to indicate \ - ..that it's attached to the previous condition. + Hint: You should probably have a ".." in front of the "else", to indicate that it's attached \ + ..to the previous condition. ") ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -164,15 +164,16 @@ test: (for $var in $iterable $body) compiles to: unless $var: at (this tree) fail "No var here" + # This uses Lua's approach of only allowing loop-scoped variables in a loop if (($var.type == "Action") and ($var.stub == "1 =")): [$key, $value] = [$var.1, $var.3] ..else: [$key, $value] = [nil, $var] - + unless $value: at (this tree) fail "No value here" - + # Numeric loop: if (($iterable.type == "Action") and (($iterable, get stub) == "1 to")): [$start, $stop] = [$iterable.1, $iterable.3] @@ -181,13 +182,15 @@ test: local _start = \($start as lua expr) for \($value as lua identifier)=_start,\($stop as lua expr) do ") + if $key: $loop, add (" - + local \($key as lua identifier) = \($value as lua identifier) - _start + 1; ") + go to (loop set) - + # Numeric loop with step: if (($iterable.type == "Action") and (($iterable, get stub) == "1 to 2 by")): [$start, $stop, $step] = [$iterable.1, $iterable.3, $iterable.5] @@ -196,13 +199,15 @@ test: local _start, _step = \($start as lua expr), \($step as lua expr); for \($value as lua identifier)=_start,\($stop as lua expr),_step do ") + if $key: $loop, add (" - + local \($key as lua identifier) = (\($value as lua identifier) - _start)/_step + 1 ") + go to (loop set) - + # for $ in (...): if $key: $loop = @@ -216,6 +221,7 @@ test: ") --- (loop set) --- + # TODO: don't always wrap in block $lua = Lua (" @@ -236,8 +242,10 @@ test: $lua, add "\n end" if ($key and ($body has subtree \(stop $key))): $lua, add "\n " (\(---stop $key ---) as lua) + if ($body has subtree \(stop $value)): $lua, add "\n " (\(---stop $value ---) as lua) + $lua, add "\nend -- for-loop" $lua, remove free vars [($value as lua identifier, text), $key and ($key as lua identifier, text)] return $lua @@ -293,7 +301,6 @@ test: repeat 5 times: $x += 1 assume $x == 5 - (repeat $n times $body) parses as (for (=lua "_i") in (1 to $n by 1) $body) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -325,41 +332,41 @@ test: for $line in $body: unless - (($line.type == "Action") and ((size of $line) >= 2)) and - $line.(size of $line) is "Block" syntax tree + (($line.type == "Action") and ((#$line) >= 2)) and + $line.(#$line) is "Block" syntax tree ..: at $line fail (" Compile error: Invalid line for the body of an 'if' block. - Hint: Each line should contain one or more conditional expressions followed \ - ..by a block, or "else" followed by a block. + Hint: Each line should contain one or more conditional expressions followed by a block, \ + ..or "else" followed by a block. ") - $action = $line.(size of $line) - if (($line.1 == "else") and ((size of $line) == 2)): + $action = $line.(#$line) + if (($line.1 == "else") and ((#$line) == 2)): unless $else_allowed: at $line fail (" Compile error: You can't have two 'else' blocks. Hint: Merge all of the 'else' blocks together. ") - unless ((size of "\$code") > 0): + unless ((#"\$code") > 0): at $line fail (" Compile error: You can't have an 'else' block without a preceding condition. - Hint: If you want the code in this block to always execute, you don't need a \ - ..conditional block around it. Otherwise, make sure the 'else' block comes last. + Hint: If you want the code in this block to always execute, you don't need a conditional \ + ..block around it. Otherwise, make sure the 'else' block comes last. ") $code, add "\nelse\n " ($action as lua) $else_allowed = (no) ..else: $code, add $clause " " - for $i in 1 to ((size of $line) - 1): + for $i in 1 to ((#$line) - 1): if ($i > 1): $code, add " or " $code, add ($line.$i as lua expr) $code, add " then\n " ($action as lua) $clause = "\nelseif" - if ((size of "\$code") == 0): + if ((#"\$code") == 0): at $body fail (" Compile error: 'if' block has an empty body. Hint: This means nothing would happen, so the 'if' block should be deleted. @@ -396,40 +403,40 @@ test: for $line in $body: unless - (($line.type == "Action") and ((size of $line) >= 2)) and - $line.(size of $line) is "Block" syntax tree + (($line.type == "Action") and ((#$line) >= 2)) and + $line.(#$line) is "Block" syntax tree ..: at $line fail (" Compile error: Invalid line for 'if' block. Hint: Each line should contain expressions followed by a block, or "else" followed by a block. ") - $action = $line.(size of $line) - if (($line.1 == "else") and ((size of $line) == 2)): + $action = $line.(#$line) + if (($line.1 == "else") and ((#$line) == 2)): unless $else_allowed: at $line fail (" Compile error: You can't have two 'else' blocks. Hint: Merge all of the 'else' blocks together. ") - unless ((size of "\$code") > 0): + unless ((#"\$code") > 0): at $line fail (" Compile error: You can't have an 'else' block without a preceding condition. - Hint: If you want the code in this block to always execute, you don't need \ - ..a conditional block around it. Otherwise, make sure the 'else' block comes last. + Hint: If you want the code in this block to always execute, you don't need a conditional \ + ..block around it. Otherwise, make sure the 'else' block comes last. ") $code, add "\nelse\n " ($action as lua) $else_allowed = (no) ..else: $code, add $clause " " - for $i in 1 to ((size of $line) - 1): + for $i in 1 to ((#$line) - 1): if ($i > 1): $code, add " or " $code, add "\(mangle "branch value") == " ($line.$i as lua expr) $code, add " then\n " ($action as lua) $clause = "\nelseif" - if ((size of "\$code") == 0): + if ((#"\$code") == 0): at $body fail (" Compile error: 'if' block has an empty body. Hint: This means nothing would happen, so the 'if' block should be deleted. |