diff options
Diffstat (limited to 'libbuild2')
| -rw-r--r-- | libbuild2/parser.cxx | 42 | ||||
| -rw-r--r-- | libbuild2/parser.hxx | 3 | ||||
| -rw-r--r-- | libbuild2/variable.hxx | 3 | ||||
| -rw-r--r-- | libbuild2/variable.txx | 27 |
4 files changed, 49 insertions, 26 deletions
diff --git a/libbuild2/parser.cxx b/libbuild2/parser.cxx index 1b4bf53..735677e 100644 --- a/libbuild2/parser.cxx +++ b/libbuild2/parser.cxx @@ -1966,9 +1966,16 @@ namespace build2 if (tt == type::newline || tt == type::eos) fail (t) << "expected " << k << "-expression instead of " << t; - // Parse as names to get variable expansion, evaluation, etc. Note - // that we also expand patterns (could be used in nested contexts, - // etc; e.g., "if pattern expansion is empty" condition). + // Parse the condition similar to a value on the RHS of an + // assignment (expansion, attributes). While at this stage the + // attribute's usefulness in this context is not entirely clear, we + // allow it for consistency with other similar directives (switch, + // for) and also who knows what attributes we will have in the + // future (maybe there will be a way to cast 0/[null] to bool, for + // example). + // + // Note also that we expand patterns (they could be used in nested + // contexts, etc; e.g., "if pattern expansion is empty" condition). // const location l (get_location (t)); @@ -1978,10 +1985,10 @@ namespace build2 // bool e ( convert<bool> ( - parse_value (t, tt, - pattern_mode::expand, - "expression", - nullptr))); + parse_value_with_attributes (t, tt, + pattern_mode::expand, + "expression", + nullptr))); take = (k.back () == '!' ? !e : e); } @@ -2531,9 +2538,9 @@ namespace build2 bool neg (t.value.back () == '!'); const location al (get_location (t)); - // Parse the next chunk as names to get variable expansion, evaluation, - // etc. Do it in the value mode so that we don't treat ':', etc., as - // special. + // Parse the next chunk (the condition) similar to a value on the RHS of + // an assignment. We allow attributes (which will only apply to the + // condition) for the same reason as in if-else (see parse_if_else()). // mode (lexer_mode::value); next (t, tt); @@ -2546,11 +2553,11 @@ namespace build2 // bool e ( convert<bool> ( - parse_value (t, tt, - pattern_mode::expand, - "expression", - nullptr, - true))); + parse_value_with_attributes (t, tt, + pattern_mode::expand, + "expression", + nullptr, + true /* chunk */))); e = (neg ? !e : e); if (e) @@ -3057,7 +3064,8 @@ namespace build2 parse_value_with_attributes (token& t, token_type& tt, pattern_mode pmode, const char* what, - const string* separators) + const string* separators, + bool chunk) { // Parse value attributes if any. Note that it's ok not to have anything // after the attributes (think [null]). @@ -3065,7 +3073,7 @@ namespace build2 attributes_push (t, tt, true); value rhs (tt != type::newline && tt != type::eos - ? parse_value (t, tt, pmode, what, separators) + ? parse_value (t, tt, pmode, what, separators, chunk) : value (names ())); if (pre_parse_) diff --git a/libbuild2/parser.hxx b/libbuild2/parser.hxx index 7174b3e..d0e5b57 100644 --- a/libbuild2/parser.hxx +++ b/libbuild2/parser.hxx @@ -342,7 +342,8 @@ namespace build2 parse_value_with_attributes (token& t, token_type& tt, pattern_mode pmode, const char* what = "name", - const string* separators = &name_separators); + const string* separators = &name_separators, + bool chunk = false); // Append names and return the indication if the parsed value is not NULL // and whether it is typed (and whether it is a pattern if pattern_mode is diff --git a/libbuild2/variable.hxx b/libbuild2/variable.hxx index 3eed61e..3cb3d7f 100644 --- a/libbuild2/variable.hxx +++ b/libbuild2/variable.hxx @@ -621,7 +621,8 @@ namespace build2 //template <typename T> T convert (names&&); (declaration causes ambiguity) // Convert value to T. If value is already of type T, then simply cast it. - // Otherwise call convert(names) above. + // Otherwise call convert(names) above. If value is NULL, then throw + // invalid_argument (with an appropriate message). // template <typename T> T convert (value&&); diff --git a/libbuild2/variable.txx b/libbuild2/variable.txx index 9b7490a..92b7169 100644 --- a/libbuild2/variable.txx +++ b/libbuild2/variable.txx @@ -60,14 +60,27 @@ namespace build2 T convert (value&& v) { - if (v.type == nullptr) - return convert<T> (move (v).as<names> ()); - else if (v.type == &value_traits<T>::value_type) - return move (v).as<T> (); + if (v) + { + if (v.type == nullptr) + return convert<T> (move (v).as<names> ()); + else if (v.type == &value_traits<T>::value_type) + return move (v).as<T> (); + } - throw invalid_argument ( - string ("invalid ") + value_traits<T>::value_type.name + - " value: conversion from " + v.type->name); + string m ("invalid "); + m += value_traits<T>::value_type.name; + m += " value: "; + + if (v) + { + m += "conversion from "; + m += v.type->name; + } + else + m += "null"; + + throw invalid_argument (move (m)); } template <typename T> |