Struct gpp::Context

pub struct Context {
    pub macros: HashMap<String, String>,
    pub inactive_stack: u32,
    pub used_if: bool,
    pub allow_exec: bool,
    pub in_stack: Vec<Child>,
}

Context of the current processing.

Contains a set of currently defined macros, as well as the number of nested if statements that are being ignored; this is so that if the parser failed an if statement, and it is currently ignoring data, it knows how many endifs it needs to encounter before resuming reading data again. Only if this value is 0 then the parser will read data. It also stores whether the current if group has been accepted; this is for if groups with over three parts.

There are no limits on what variable names can be; by directly altering Context::macros, you can set variable names not possible with #defines. However, when replacing variable names in text the variable name must be surrounded by two characters that are not alphanumeric or an underscore.

Fields

macros: HashMap<String, String>

Map of all currently defined macros.

inactive_stack: u32

Number of layers of inactive if statements.

used_if: bool

Whether the current if statement has been accepted.

allow_exec: bool

Whether #exec and #in commands are allowed.

in_stack: Vec<Child>

The stack of processes that #in is piping to.

Methods

impl Context

pub fn new() -> Context

Create a new empty context with no macros or inactive stack and exec commands disallowed.

pub fn new_exec() -> Context

Create a new empty context with no macros or inactive stack and exec commands allowed.

pub fn from_map(macros: HashMap<String, String>) -> Context

Create a context from an existing HashMap

pub fn from_vec(macros: Vec<(&str, &str)>) -> Context

Create a context from a vector of tuples

Trait Implementations

impl Default for Context

fn default() -> Context

Returns the "default value" for a type.