Boost.Phoenix is a C++ library to enable function programming in C++.
Questions tagged [boost-phoenix]
159 questions
4
votes
1 answer
Obtaining the types of local variables in Boost Phoenix
How can I obtain the types of the local variables used within a scoped Boost Phoenix statement? Using Phoenix and Proto I can extract numerous aspects of a Phoenix expression. For example, the following code exposes the arity (3); tag type…
user2023370
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4
votes
2 answers
Calling a function from within a boost::phoenix::lambda
I am trying to use boost::phoenix to emulate C++ lambda expressions on an older compiler that lacks C++11 support, and I am unable to call a simple function from within a lambda expression.
C++11 Version:
[](unsigned a) { foo( a ); }( 12678u ); //…
mark
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4
votes
1 answer
boost::spirit: multiple statements in semantic action block
boost::phoenix defines statement blocks using the operator "," (see boost phoenix block statements). I'm trying to use this construct in the semantic action part of a boost::spirit rule. However, it looks like only the last statement in the…
mvc
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3
votes
1 answer
Boost Phoenix (or Boost Lambda) - taking a pointer lazily
Is there a way of taking a pointer of a lazy phoenix value / ref ? If so how ?
Hassan Syed
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3
votes
1 answer
Using lambdas or external functions as spirit.qi semantic actions
Iʼm playing with creating Boost.Spirit.Qi-based parsing. Having an example like calc_utree, I'm trying to extend what to use as semantic action.
It's trivial to reuse the same approach with an alone assignment as semantic action, for example
…
Netch
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3
votes
1 answer
Boost Spirit tokenise expression into vector
I am trying to parse an expression which can also contain identifiers and push each element into an std::vector , and I have come up with the following grammar:
#include
#include…
Razvan Meriniuc
- 33
- 2
3
votes
1 answer
Parsing simple csv table with boost-spirit
I was trying to use boost-spirit to parse a fairly simple cvs file format.
My csv file looks like this:
Test.txt
2
5. 3. 2.
6. 3. 6.
The first integer represents the number of lines to read and each line consists of exactly three double…
Aleph0
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3
votes
0 answers
Too many constructions with phoenix::new_ in boost spirit grammar
I'm quite new to the spirit framework, and I'd like to ask you a question concerning my program.
My idea is to implement the C- programming language grammar into spirit (link is here http://marvin.cs.uidaho.edu/Teaching/CS445/c-Grammar.pdf).
I'm…
bob
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- 3
3
votes
1 answer
how to access elements of a tuple in a semantic action
My grammar has various entries which start with a generic name.
After I determined the type I would like to use the expectation operator in order to create parsing errors.
rule1=name >> (type1 > something);
rule2=name >> (type2 > something);
I…
user6520006
3
votes
1 answer
Boost Spirit rule with custom attribute parsing
I am writing a Boost Spirit grammar to parse text into a vector of these structs:
struct Pair
{
double a;
double b;
};
BOOST_FUSION_ADAPT_STRUCT(
Pair,
(double, a)
(double, a)
)
This grammar has a rule like…
AJM
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3
votes
2 answers
C++ boost::lambda::ret equivalent in phoenix
Boost lambda allows to overwrite deduced return type using ret template.
I have tried searching for equivalent in phoenix but could not find one.
Is there an equivalent in phoenix? I know how to make my own Replacement but I would rather not. …
Anycorn
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3
votes
1 answer
boost spirit karma generation from a collection of struct using a member function
I am trying to use karma to generate a comma separated list of strings, from a vector of structs that contain a member function that provides the string.
While I can generate single string output using phoenix::bind, and I can generate a csv output…
nostep
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3
votes
1 answer
How to implement a lambda function for a sort algorithm involving object members, indirection, and casting?
I'm working on some code and I have a section where I do a one off sort function. To implement it I decided it was easiest to overload the operator< function. What I would prefer to do is move the implementation of the sort closer to the actual call…
ApockofFork
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3
votes
1 answer
BOOST_PHOENIX_ADAPT_FUNCTION(...) with templated function on templated container
I need a lazy evaluating version of std::pair.first. My approach is to use boost::phoenix, define a templated function and use the BOOST_PHOENIX_ADAPT_FUNCTION makro as folows:
template
T1 first_impl(std::pair p){
…
Dirk
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3
votes
1 answer
Updating synthesized attribute value from semantic action
I want to understand what exactly happens under the hood of boost::spirit::qi. Suppose we have simple parser that parses and calculates expressions consisting of numbers and add/subtract operations:
int main()
{
std::string INPUT_DATA = "12e-1 +…
n0rd
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