IBP banding data system: Internal maintenance specification

This static method processes a page header line. We assume that the initial PAGE_SYMBOL character has already been skipped.

# - - -   P a g e H e a d e r . s c a n L i n e   - - -

    @staticmethod
    def scanLine(compiler, scan):
        '''Scan a page header line.
        '''
        #-- 1 --
        # [ fieldList  :=  fields from the line in scan that are
        #       separated by clumps of whitespace, uppercased ]
        fieldList = scan.line[scan.pos:].upper().split()

See Section 24.3, “PageHeader.checkSite(): Verify correct location or station”.

        #-- 2 --
        # [ if fieldList has exactly three members ->
        #     rawSite  :=  fieldList[0]
        #     rawSize  :=  fieldList[1]
        #     rawPageNo  :=  fieldList[2]
        #   else ->
        #     Log()  +:=  error message
        #     raise SyntaxError ]
        if  len(fieldList) == 3:
            rawSite, rawSize, rawPageNo = fieldList
        else:
            message  = ("Expecting three fields (station or location, "
                "band size, and page number.")
            scan.syntax(message)

        #-- 2 --
        # [ if rawSite does not match the compiler's location or
        #   station code ->
        #     Log()  +:=  error message
        #     return
        #   else -> I ]
        if  not PageHeader.checkSite(compiler, scan, rawSite):
            return

        #-- 3 --
        # [ if rawSize is longer than BAND_SIZE_L ->
        #     Log()  +:=  error message
        #     return
        #   else -> I ]
        if  len(rawSize) > BAND_SIZE_L:
            message  = ("Band size field '%s' too long; maximum "
                "%d." % (rawSize, BAND_SIZE_L))

        #-- 4 --
        # [ if rawPageNo is longer than PAGE_NO_L ->
        #     Log()  +:=  error message
        #     return
        #   else -> I ]
        if  len(rawPageNo) > PAGE_NO_L:
            message  = ("Page number field '%s' too long; maximum "
                "%d." % (rawPageNo, PAGE_NO_L))

See Section 24, “class PageHeader: Page header line object”.

        #-- 5 --
        # [ return a new PageHeader object with size=rawSize and
        #   pageNo=rawPageNo ]
        return  PageHeader(rawSize, rawPageNo)