Struct Writer 

pub struct Writer<W: Write> { /* private fields */ }

Struct wrapping an std::io::Write with methods for writing VCD commands and data.

Example

use std::{fs::File, io::BufWriter};
use vcd::{Value, TimescaleUnit};
 
let mut writer = vcd::Writer::new(BufWriter::new(File::create("test.vcd")?));
 
writer.timescale(1, TimescaleUnit::US)?;
writer.add_module("top")?;
let clock = writer.add_wire(1, "clock")?;
writer.upscope()?;
writer.enddefinitions()?;
 
let mut t = 0;
while t < 100 {
    writer.timestamp(t)?;
    writer.change_scalar(clock, Value::V0)?;
    t += 2;
 
    writer.timestamp(t)?;
    writer.change_scalar(clock, Value::V1)?;
    t += 2;
}

Implementations

impl<W: Write> Writer<W>

pub fn new(writer: W) -> Writer<W>

Creates a Writer wrapping an io::Write.

let mut buf = Vec::new();
let mut vcd = vcd::Writer::new(&mut buf);

pub fn writer(&mut self) -> &mut W

Get the wrapped io::Write.

pub fn flush(&mut self) -> Result<()>

Flush the wrapped io::Write.

pub fn header(&mut self, h: &Header) -> Result<()>

Writes a complete header with the fields from a Header struct from the parser.

pub fn comment(&mut self, v: &str) -> Result<()>

Writes a $comment command.

pub fn date(&mut self, v: &str) -> Result<()>

Writes a $date command.

pub fn version(&mut self, v: &str) -> Result<()>

Writes a $version command.

pub fn timescale(&mut self, ts: u32, unit: TimescaleUnit) -> Result<()>

Writes a $timescale command.

pub fn scope_def(&mut self, t: ScopeType, i: &str) -> Result<()>

Writes a $scope command.

pub fn add_module(&mut self, identifier: &str) -> Result<()>

Writes a $scope command for a module.

Convenience wrapper around Writer::scope_def.

pub fn upscope(&mut self) -> Result<()>

Writes an $upscope command.

pub fn scope(&mut self, s: &Scope) -> Result<()>

Writes a $scope command, a series of $var commands, and an $upscope commands from a Scope structure from the parser.

pub fn var_def( &mut self, var_type: VarType, width: u32, id: IdCode, reference: &str, index: Option<ReferenceIndex>, ) -> Result<()>

Writes a $var command with a specified id.

pub fn add_var( &mut self, var_type: VarType, width: u32, reference: &str, index: Option<ReferenceIndex>, ) -> Result<IdCode>

Writes a $var command with the next available ID, returning the assigned ID.

Convenience wrapper around Writer::var_def.

pub fn add_wire(&mut self, width: u32, reference: &str) -> Result<IdCode>

Adds a $var for a wire with the next available ID, returning the assigned ID.

Convenience wrapper around Writer::add_var.

pub fn var(&mut self, v: &Var) -> Result<()>

Writes a $var command from a Var structure from the parser.

pub fn enddefinitions(&mut self) -> Result<()>

Writes a $enddefinitions command to end the header.

pub fn timestamp(&mut self, ts: u64) -> Result<()>

Writes a #xxx timestamp.

pub fn change_scalar<V: Into<Value>>(&mut self, id: IdCode, v: V) -> Result<()>

Writes a change to a scalar variable.

pub fn change_vector( &mut self, id: IdCode, v: impl IntoIterator<Item = Value>, ) -> Result<()>

Writes a change to a vector variable.

pub fn change_real(&mut self, id: IdCode, v: f64) -> Result<()>

Writes a change to a real variable.

pub fn change_string(&mut self, id: IdCode, v: &str) -> Result<()>

Writes a change to a string variable.

pub fn begin(&mut self, c: SimulationCommand) -> Result<()>

Writes the beginning of a simulation command.

pub fn end(&mut self) -> Result<()>

Writes an $end to end a simulation command.

pub fn command(&mut self, c: &Command) -> Result<()>

Writes a command from a Command enum as parsed by the parser.