haste-compiler-0.2.5: lib/Handle.js

// Simulate handles.
// When implementing new handles, remember that passed strings may be thunks,
// and so need to be evaluated before use.

function jsNewHandle(init, read, write, flush, close, seek, tell) {
    var h = {
        read: read || function() {},
        write: write || function() {},
        seek: seek || function() {},
        tell: tell || function() {},
        close: close || function() {},
        flush: flush || function() {}
    };
    init.call(h);
    return h;
}

function jsReadHandle(h, len) {return h.read(len);}
function jsWriteHandle(h, str) {return h.write(str);}
function jsFlushHandle(h) {return h.flush();}
function jsCloseHandle(h) {return h.close();}

function jsMkConWriter(op) {
    return function(str) {
        str = E(str);
        var lines = (this.buf + str).split('\n');
        for(var i = 0; i < lines.length-1; ++i) {
            op.call(console, lines[i]);
        }
        this.buf = lines[lines.length-1];
    }
}

function jsMkStdout() {
    return jsNewHandle(
        function() {this.buf = '';},
        function(_) {return '';},
        jsMkConWriter(console.log),
        function() {console.log(this.buf); this.buf = '';}
    );
}

function jsMkStderr() {
    return jsNewHandle(
        function() {this.buf = '';},
        function(_) {return '';},
        jsMkConWriter(console.warn),
        function() {console.warn(this.buf); this.buf = '';}
    );
}

function jsMkStdin() {
    return jsNewHandle(
        function() {this.buf = '';},
        function(len) {
            while(this.buf.length < len) {
                this.buf += prompt('[stdin]') + '\n';
            }
            var ret = this.buf.substr(0, len);
            this.buf = this.buf.substr(len);
            return ret;
        }
    );
}